Protecting a Bank [3.5, E6]

[Morof Stonehands]

I’m currently brainstorming ideas on making a bank for my world, and I figured I’d see what other people have done in regards to protecting said bank.

It will be, for the most part, a place where people store their valuables, plus some letters of credit and loans. But since storage is the priority, what are some good ideas for keeping everyone’s gold, gems, and items safe from thieves? Mind you it is E6 so no spells above 3rd level exist.

[FactualArcher]

Traps are great for this sort of thing. The spell Alarm is also nice, and affordable even at E6. If possible, protection from Evil is nice on guards. Also, filling the vault with zombies is fun, though creating them is a lot harder in E6.

[thethird]

Dragons.

You've got a lot of coins in one place, that sounds like a hoard. The bank gives a strip of paper as a proof of credit. The bank also invests in adventures to collect more riches and increase the hoard. There is also a side business in insurance.

[AvatarVecna]

E6? Do you uh...do you actually need anything special? You're rarely going to run into somebody who has magic at all, let alone the magical power necessary to pierce utterly-mundane bank defenses. A quick glance in the Stronghold Builder's Guidebook indicates a solid iron door with a DC 40 adamantine lock will cost you 2000 gp. SBG has a lot of useful material for vault-building actually.

[Anthrowhale]

Permeable Form provides a deep penetration ability, so it seems important to have active defenses.

[Mechalich]

E6? Do you uh...do you actually need anything special? You're rarely going to run into somebody who has magic at all, let alone the magical power necessary to pierce utterly-mundane bank defenses. A quick glance in the Stronghold Builder's Guidebook indicates a solid iron door with a DC 40 adamantine lock will cost you 2000 gp. SBG has a lot of useful material for vault-building actually.

Depending on how E6 is constructed magic is merely less powerful, not less abundant. Even significantly reducing the number of spellcasters still leaves a divine caster in every village and an arcane caster in every town. They'll mostly be level 1 or 2, and many will be adepts as opposed to more potent caster classes, but they'll still be around. There are also a number of low-power monsters that represent significant threats to this kind of enterprise, such as Dopplegangers.

One thing you'd want is a caster or casters who are trusted completely to utilize Zone of Truth on anyone who accesses the vaults. Since this is a divine spell, it makes a certain amount of intuitive sense to have the bank simply be a temple of an appropriately oriented god (in fact it's quite probable that all banks would be such and that the relevant faith would have something of a stranglehold on the financial system).

[AvatarVecna]

Depending on how E6 is constructed magic is merely less powerful, not less abundant. Even significantly reducing the number of spellcasters still leaves a divine caster in every village and an arcane caster in every town. They'll mostly be level 1 or 2, and many will be adepts as opposed to more potent caster classes, but they'll still be around. There are also a number of low-power monsters that represent significant threats to this kind of enterprise, such as Dopplegangers.

One thing you'd want is a caster or casters who are trusted completely to utilize Zone of Truth on anyone who accesses the vaults. Since this is a divine spell, it makes a certain amount of intuitive sense to have the bank simply be a temple of an appropriately oriented god (in fact it's quite probable that all banks would be such and that the relevant faith would have something of a stranglehold on the financial system).

1) "Not less abundant". Magic is pretty un-abundant by default, at least among people. It's extremely common among adventurers, but among civilians it's much lower. You're talking about a divine caster in every village, as if that's not "1 per 1000 people". We can go over how actually-common magic is, but that's a little irrelevant because...

2) You're overly focusing on the "you're rarely going to run into somebody who has magic at all" and completely ignoring the far more important "let alone the magical power necessary to pierce utterly-mundane bank defenses".

Disguise Self is a quick disguise with an extra +10 over your normal check, that can't be cast on somebody else. It does nothing to help your bluff check, and it's a purely illusory disguise so vulnerable to physical inspection. Casters with both bluff and disguise is basically just bards...and in a default setting with no level cap, "bards capable of 1st lvl spells" are about 1 person out of every 400. And that's not "1 in 400 people is a bardic master of disguise". That's "1 in 400 people are a bard who could theoretically be a master of disguise". Not every Bard 2+ is going to have Bluff or Disguise trained, or know the spell. The actual ratio, whatever it is, will be a lot lower than 1 in 400.

Well maybe you could get a rogue with a hat of disguise! You could have even a rogue 1 with decent bluff and disguise do the job. Sure. But 1 in 150 people are rogues at all, and again that's "rogues", not "rogueish masters of disguise". Lots of kinds of rogues. And of course, level 1 rogues aren't necessarily the kind of person you'd hand a 12000 dollar hat to. You'd wanna splurge for someone with a bit more skill, to really be sure of yourself. In normal D&D world, it's about an even split between "rogues lvl 1-5" and "rogues lvl 6+". So about 1 in 300 are professional rogues of some kind (not specifically masters of disguise) before we even get into whatever changes are made going from normal world to E6.

This problem echoes across most spells. Invisibility can't get you past a locked door, and if you're not also silenced it probably can't get you past the guards either. You need to put it on someone who's already sneaky. Charm Person to get the bank manager to let you in doesn't give you a safe deposit box key. Knock can't penetrate a portcullis, and only penetrates two defenses per casting anyway, so layered doors into the vault that includes a portcullis will keep it at bay, especially if they can include arcane locks. Even a sorcerer 6 can't just blast through a good wall, and even an adamantine weapon will take a good amount of time to get through most walls (assuming the wall isn't tough enough that its hardness comes into play, at which point it takes an eternity to get through). Even a barbarian 6 is gonna have trouble with a dozen basic guards, let alone professional soldiers like a big bank could afford. Even a rogue 6 isn't going to be so skillful that they can bet on outskilling a half-dozen people all at once, because they're still at low enough bonuses that the die rolls involved actually matter. Doppleganger has the same problem: for all their arrogance, at their best they've got Bluff +14. Their disguise will probably be impenetrable to normal perception, but a simple interview will feature enough lies for them to roll low and guards to roll high and then the jig is up. This is without even touching on how common dopplegangers even are, which we don't really have numbers on the same way we do classes and levels.

The worst E6 gets is a team of professional rogues well-equipped with magical gear capable of things real-world technology isn't...at which point it's basically just a heist movie with magic instead of tech. If you put in that level of effort, yeah you can get into even extremely secure vaults. But the vast majority of the world's population can't even consider being a part of that team. And any team capable of robbing the king's vault is also capable of clearing out a dungeon, which is likely to be far more lucrative anyway and doesn't come with severe social consequences for getting caught (and is probably about as dangerous as trying to rob the king).

Solid walls. Layered doors. Difficult locks. Watchful guards. This will keep 99.99% of people from even being able to consider breaking in.

[Maat Mons]

What's the approximate total value of the contents of the vault going to be? That would place an upper limit on how much anyone is going to be willing to spend protecting it.

[Morof Stonehands]

Traps are great for this sort of thing. The spell Alarm is also nice, and affordable even at E6. If possible, protection from Evil is nice on guards. Also, filling the vault with zombies is fun, though creating them is a lot harder in E6.

Zombie is a solid idea, and strangely enough one I hadn’t considered!


Dragons.

You've got a lot of coins in one place, that sounds like a hoard. The bank gives a strip of paper as a proof of credit. The bank also invests in adventures to collect more riches and increase the hoard. There is also a side business in insurance.

Only problem I see is when an adventurer comes to collect his spare items and the dragon says no haha


E6? Do you uh...do you actually need anything special? You're rarely going to run into somebody who has magic at all, let alone the magical power necessary to pierce utterly-mundane bank defenses. A quick glance in the Stronghold Builder's Guidebook indicates a solid iron door with a DC 40 adamantine lock will cost you 2000 gp. SBG has a lot of useful material for vault-building actually.

SBG is a book I often forget about, I’ll have to check it out. As for special things yeah one might actually need those. Looking at banking as a service, for higher paying customers they might want something a little extra.


Depending on how E6 is constructed magic is merely less powerful, not less abundant. Even significantly reducing the number of spellcasters still leaves a divine caster in every village and an arcane caster in every town. They'll mostly be level 1 or 2, and many will be adepts as opposed to more potent caster classes, but they'll still be around. There are also a number of low-power monsters that represent significant threats to this kind of enterprise, such as Dopplegangers.

One thing you'd want is a caster or casters who are trusted completely to utilize Zone of Truth on anyone who accesses the vaults. Since this is a divine spell, it makes a certain amount of intuitive sense to have the bank simply be a temple of an appropriately oriented god (in fact it's quite probable that all banks would be such and that the relevant faith would have something of a stranglehold on the financial system).

Zone of truth is a good idea, placed like a metal detector would be!


What's the approximate total value of the contents of the vault going to be? That would place an upper limit on how much anyone is going to be willing to spend protecting it.

Unknown, honestly. Im picturing more of a service like I mentioned above. Most people will pay the fee for their deposit box behind a locked door, but the 1% is gonna want something a little more secure

[AvatarVecna]

What's the approximate total value of the contents of the vault going to be? That would place an upper limit on how much anyone is going to be willing to spend protecting it.

Hard to say exactly. Part of the issue is that one great defense against having the bank robbed is to not have all your money in one place. You don't have one vault, you have fifty scattered around the metropolis. This makes it more convenient for the populace to access their money, and harder for someone to just steal everything really quickly. But also, while we have numbers on the amount of ready cash in a community, that's in total, not what's sitting in the bank, so it's gonna include all the pocket change and rainy day funds and mattress banks.


To determine the amount of ready cash in a community, or the total value of any given item of equipment for sale at any given time, multiply half the gp limit by 1/10 of the community’s population. For example, suppose a band of adventurers brings a bagful of loot (one hundred gems, each worth 50 gp) into a hamlet of 90 people. Half the hamlet’s gp limit times 1/10 its population equals 450 (100 ÷ 2 = 50; 90 ÷ 10 = 9; 50 × 9 = 450). Therefore, the PCs can only convert nine of their recently acquired gems to coins on the spot before exhausting the local cash reserves. The coins will not be all bright, shiny gold pieces. They should include a large number of battered and well-worn silver pieces and copper pieces as well, especially in a small or poor community. If those same adventurers hope to buy longswords (price 15 gp each) for their mercenary hirelings, they’ll discover that the
hamlet can offer only 30 such swords for sale, because the same 450 gp limit applies whether you’re buying or selling in a given community.

Because of the second example, we can probably use the Ready Cash as an upper limit on vault costs. You can't buy more than 450 gp worth of longswords, and you can't buy more than 450 gp worth of locks/vaults/chests/etc. Makes sense to me. And while the vault can contain less than the Ready Cash in actual cash (if people dont keep all their money in the bank), it can't have more than that even if it's got the capacity, because then the community would have more ready cash than it should. It can have other goods stored in there, though.

Ready Cash based on community size:

Thorp (20-80): 40 - 160 gp (2 gp per citizen)
Hamlet (81-400): 405 - 2,000 gp (5 gp per citizen)
Village (401-900): 4,010 - 9,000 gp (10 gp per citizen)
Small Town (901-2,000): 36,040 - 80,000 gp (40 gp per citizen)
Large Town (2,001-5,000): 300,150 - 750,000 gp (150 gp per citizen)
Small City (5,001-12,000): 3,750,750 - 9,000,000 gp (750 gp per citizen)
Large City (12001-25000): 24,002,000 - 50,000,000 gp (2000 gp per citizen)
Metropolis (25001+): 125,005,000 gp or more (5,000 gp per citizen)

Gut says that it's not until you get up to about a small town that a bank gets truly justified.

Let's take a village of 500, averaging 10 gp worth per citizen. Let's call it 9 gp for most of the citizens, and then three rulers (local nobility, canny merchant, spiritual leader) each taking an even share of the remainder (170 gp worth each or thereabout). Each of those citizens is probably looking at 300 cp/30 sp/3 gp scattered around their family home for them. It's not quite 7 lbs of coins per person, not exactly banking material. The local rulers are probably looking at about 4000 cp/400 sp/40 gp/5 pp each. A little under 90 lbs of coins for each of them, a half-full chest for each of them. More likely, they've got a small chest they keep most of the smaller denominations in, and then have an even mix of each coinage that they bring around with them for day-to-day stuff as needed. Maybe keep the platinums somewhere secret, but probably not in the "heavy chest of coppers for a rainy day" location.

EDIT: A metropolis with probably dozens of bank locations, each containing no more than a few million in their particular vault, will still warrant some pretty expensive vaults per location for protecting all the shinies. Small Town probably has one bank with a decent vault. Hmm...

[Inevitability]

Doppelgangers have been mentioned: Discern Shapechanger is a 2nd-level wizard spell and offers no save, though it does have an expensive material component.

A trick I used for the Cerebrex Iron Chef round was to cast Rage on potentially untrustworthy people: because Bluff is charisma-based, this prevents lies even more comprehensively than Zone of Truth would, assuming you have some way of confirming whether the target is truly affected (A DC 25 Sense Motive to detect enchantments should work if nothing else does, which can be reliably made using a specialized build or something like Guidance of the Avatar).

[AvatarVecna]

Let's go with a Large Town with a middling population (3500 people), so can't spend more than 525000 gp on the bank.

Step 1: Select A Site

Within 1 mile of Small Town: +0%
Temperate: +0%
No Special Features: +0%

Let's assume nothing that impacts the price of the building. We're not building somewhere weird, we're a bank in the town. It doesn't cost more, it doesn't cost less. Fair.

Step 2: Choose A Size

DMG2 business rules indicate that a Moneylending business (which a bank almost certainly counts as) should be at least a Grand House with at least 5 employees. Grand House is the example for 7 stronghold spaces. Mansion would be 15 but that feels excessive. Let's not go higher than that.

Step 3: Purchase Components and Walls

Barracks: 5 bunk beds for 10 guards/soldiers. 400 gp/1ss.

Bath, Basic: This is the customer bathroom, employees have their own elsewhere in the building. 400 gp/0.5ss.

Bedroom Suite, Basic: A more private quarters for the head of security. 800 gp/1ss.

Bedroom Suite, Fancy: A nice place for the bank manager to live when not on-the-job elsewhere in the building. 5000 gp/1ss.

Dining Hall, Basic: Seats 30 comfortably, requires a kitchen. 2000 gp/2ss.

Kitchen, Basic: Feeds 15, requires a cook. 2000 gp/1ss.

Servant's Quarters: Room for 6 servants. 400 gp/1ss.

Shop, Luxury: This, paired with storage, is recommended by the book for running a bank. Requires two clerks, and two guards per shift. 16000 gp/1ss.

Storage, Luxury: All the storage options have similar capacity, this one is just fancy in a way that matches the shop. Requires one clerk. 3000 gp/1ss.

Study/Office, Fancy: This will be where the head of security does his business most of the day. He can interview new hires here, lock down an attempted thief until the authorities arrive, check to make sure people wanting to access the vault are who they claim to be, or just be immediately on hand next to the main business part of the building. 2500 gp/1ss.

Study/Office, Luxury: The bank manager's office, for meeting with important clients. Requires one clerk. 15000 gp/1.5ss.

After purchasing components, here are our totals:

47500 gp
12 stronghold spaces
6 guards minimum
4 clerks minimum
1 cook minimum


12ss will be 40% interior walls and 60% exterior walls. Let's make exterior walls magically-treated iron (primarily to make the vault hard to break into); this would be 60% times 18000 gp x 12ss = 129600 gp. Interior walls will be wood; this would be 40% times 1000 gp x 12ss = 4800 gp.

We've got a total of 24 doors and 12 windows to work with. By default, they're wooden doors and shuttered windows for free. We want more security than that; even the bathrooms should be hard to break into. Let's chart it out:



Component
Doors
Windows


Barracks (2d/1w)
(2) Iron Door + Average Iron Lock
(1) Barred Window + Average Iron Lock


Bath, Basic (1d/0w)
(1) Iron Door + Simple Iron Lock



Bedroom Suite, Basic (2d/1w)
(2) Iron Door + Average Iron Lock
(1) Good Shuttered Window + Average Iron Lock


Bedroom Suite, Fancy (2d/2w)
(2) Iron Door + Good Mithral Lock
(2) Good Shuttered Windows + Average Iron Lock


Dining Hall, Basic (4d/2w)
(3) Iron Door + Average Iron Lock
(1) Portcullis + Amazing Adamantine Lock
(2) Barred Windows + Average Iron Lock


Kitchen, Basic (2d/1w)
(2) Iron Door + Simple Iron Lock
(1) Barred Window + Average Iron Lock


Servant's Quarters (2d/1w)
(2) Iron Door + Simple Iron Lock
(1) Barred Window + Average Iron Lock


Shop, Luxury (3d/2w)
(2) Iron Door + Good Mithral Lock
(1) Portcullis + Amazing Adamantine Lock
(2) Barred Windows + Good Mithral Lock


Storage, Luxury (3d/0w)
(2) Iron Door + Amazing Adamantine Lock
(1) Portcullis + Amazing Adamantine Lock



Study/Office, Fancy (2d/0w)
(1) Iron Door + Good Mithral Lock
(1) Portcullis + Amazing Adamantine Lock



Study/Office, Luxury (1d/2w)
(1) Iron Door + Good Mithral Lock
(2) Fancy Stained Glass Windows




(20) Iron Door: 20 x 500 = 10000 gp
(4) Portcullis: 4 x 750 = 3000 gp
(5) Simple Iron Lock: 5 x 20 = 100 gp
(15) Average Iron Lock: 15 x 40 = 600 gp
(8) Good Mithral Lock: 8 x 400 = 3200 gp
(6) Amazing Adamantine Lock: 6 x 1500 = 9000 gp

For people on-site, we've got the bank manager, who makes money via business rules. Their employees are 1 Adventurer (head of security), 4 Clerks (clerks and secretaries), 1 Cook (...the cook), and eight Military Officers serving as more personable guards than default. The head of security is generally around, and there will be a couple guards on duty at any given time, with the other 6 elsewhere in the building. We're going with 9 security instead of the minimum 6 needed for shifts in case some get sick or fired. Gear upfront for a military officer will generally run you about 237 gp per person. The head of security is a more seasoned professional adventurer, with no gear or level guidelines. Assuming a lvl 3 NPC (reasonable for a settlement this size) of whatever PC class you prefer, they'll have about 2500 gp worth of stuff.

8 x 237 = 1896 gp
1 x 3300 = 2500 gp

it generally takes a year for a business to get up off the ground properly, so let's factor in a year's worth of wages.

(1) Adventurer: 1 x 30 x 12 = 360 gp
(4) Clerk: 4 x 12 x 12 = 576 gp
(8) Military Officer: 8 x 18 x 12 = 1728 gp

Step 4: Purchase Extras & Wondrous Architecture

Improved Arcane Lock on all three vault doors, allowing the bank manager, head of security, and three clerks to pass through without having to break it down. Customers wait outside while the clerks (and sometimes, the head of security) fetch whatever is requested from within the vault. If there is too much of a change in staff, these spells will need to be redone. Let's assume one initial casting, and then two recastings per year to account for changes in staff. With our assumed one year of start-up time, that's thrice so far. 3 x 175 = 525 gp. Presumably the scrolls or wizards used for this were called in from the banking guild of a larger settlement (of which this is just one branch).

A continuous flame torch runs you about 110 gp per torch. Let's go with 40 of them: 3 per ss (since we need some on the outside), and then some extras for carrying around on patrols occasionally. 40 x 110 = 4400 gp.

A self-resetting "Zone Of Truth" magic trap inside the Head Of Security's office would run you 3000 gp. Useful for interviewing new hires and possible shapeshifters trying to illegally access vault contents.

Putting it all together, this bank would run you about 222785 gp within the first year. 42% of the spending limit, should be perfectly fine to get it set up here. You could probably add more defenses, particularly magic defenses, but this or something very similar would be a very self-contained and secure bank. If adapting for a small town, you probably need to limit it to the two offices, the vault, and the store, and have everybody just live somewhere else. But this is more fun to me.

The bank vault can store about 3000 cubic feet worth of valuables. Using someone else's math on coin-stacking stuff (https://rpg.stackexchange.com/questions/148012/how-do-i-calculate-the-volume-of-a-given-quantity-of-coins)...


Non-round shapes would improve the packing density to varying degrees depending on the exact shape of the coin, but using round coins seems a sensible default. So taking that into consideration:

Copper - ~22,000 coins per cubic foot (neatly stacked) - ~16,800 coins per cubic foot (loose jumble)
Silver - ~25,740 coins per cubic foot (neatly stacked) - ~19,650 coins per cubic foot (loose jumble)
Gold - ~47,400 coins per cubic foot (neatly stacked) - ~36,180 coins per cubic foot (loose jumble)
Platinum - ~52,630 coins per cubic foot (neatly stacked) - ~40,180 coins per cubic foot (loose jumble)

The community's limit on ready cash is 525,000 gp. If every speck of that was in this vault, and it was all in copper pieces, that would take up 2386 cubic feet of space. More likely, the pure cash is in mixed denominations, and the vault is just also containing a whole lot of non-cash goods - gems, pieces of artwork, magic items, and the like. A good deal of it is also probably empty for the sake of new customers.

EDIT:

Now let's make one for a metropolis; assuming a population of 43200, Ready Cash limit of 216 million. Not just a bank, but the center for a full-blown banking guild.

"If you go the largest city on the continent, you'll probably be surprised and maybe even a little disappointed to find that what few banks you've even founds in the city aren't all that different from the one in your hometown. Solid steel walls, barred windows, a standard triple-door system on a standard-size vault. Perfectly fine for most people's safe-storage needs, but you're important now, an adventurer of great repute. You've seen firsthand what determination and skill can do to far more deadly defenses than any of those civilian vaults can legally muster. Maybe you're even the kind of person who could break in if you wanted. You want to know your money isn't going anywhere you don't want it to, let alone dangerous recovered artifacts you can't let fall back into the hands of evil overlords."

"You ask your contacts, and they inform you that the local banking guild - a slightly-oversized normal bank - is actually the tip of a massive underground iceberg of a location. Dwarves carved the whole thing out of the solid stone mountain that lies beneath the city, and fortified it with materials you've never even heard of, for the express purpose of providing layers of protection to clients dissatisfied with standard vaults."

Step 1: Select A Site

Temperate: +0%
Underground: +10%
Site Hidden From Long-Range Observation: +5%

total +15%

Step 2: Choose A Size

43200/3500 = 12.34 ish

To have a similar portion of the population, and to give them a proportional base of power, let's estimate a staff of 185 and a structure of 150ss and see where that takes us.

Step 3: Purchase Components & Walls



Component
Quantity
GP/Q
ss/Q
GP
ss
Requirements
Notes


Armory, Fancy
4
2000
1
8000
4

Arm and armor 100 soldiers in style


Barracks
10
400
1
4000
10

House 100 soldiers


Bath, Fancy
2
2000
1
4000
2




Bedroom Suite, Fancy
2
5000
1
10000
2

Houses 2 librarians


Bedroom Suite, Luxury
12
25000
2
300000
24
(12) Valet
Houses 12 adventurers


Bedrooms, Fancy
24
4000
1
96000
24

Houses 48 clerks and scribes


Common Area, Fancy
15
3000
1
45000
15

Split across five meeting rooms (1/2/3/4/5)
Used for meeting with groups of clients
Used for educating new clerks
Used for divvying inheritance


Dining Hall, Fancy
7
50000
2
350000
14
Luxury Kitchen
(14) Servant
Seats 210 people in total at various small tables


Kitchen, Luxury
2
50000
2
100000
4
(12) Cook
Can feed 200


Library, Luxury
1
15000
2
15000
2
(1) Librarian



Servants' Quarters
7
400
1
2800
7

Houses 42 servants


Shop, Luxury
10
16000
1
160000
10
(20) Clerk
(100) Guard



Storage, Luxury
10
3000
1
30000
10
(10) Clerk
3000 cubic feet of storage


Study/Office, Basic
6
200
0.5
1200
3

Scribe offices


Study/Office, Fancy
2
2500
1
5000
2

Librarian offices


Study/Office, Luxury
12
15000
1.5
180000
18
(12) Clerk
Adventurer offices




151ss and 200 people. A bit higher than originally estimated but it's fine. Total component cost is 1,311,000 gp.

10 storage spaces, split up as follows:

General Use (2ss)

This is a general-use vault for the public, same as most any banking location except for being twice as large as normal. It is on the surface.

Book Storage (1ss)

The knowledge of the past is to be treasured and very carefully copied. To that end, the banking guild has a special vault designed specifically for the storage of tomes. This vault is beneath the library, which is itself beneath the surface. The library is full of copies carefully created by the scribes working for the guild. These copies will either be kept in storage so as not to depreciate the value of the original copies donated, or will be sent out to select, trusted partner libraries elsewhere in the world, such that copies of particularly rare tomes can be stored. Some tomes are in good enough condition to be copied by hand, although scribes are still be treat the originals carefully. For some originals, they are in such bad shape that magic must be used: a wand of Amaneunsis is occasionally procured for a perfect, contact-free copy method. The library and its book vault are close to the surface primarily because this part of the structure is a space provided by the banking guild to the bookbinding guild, who provide the workers and expertise for this duty, such that the banking guild won't be stepping on their toes or prioritizing profit over the preservation of knowledge.

Art Storage (1ss)

Similar to the above, it is best to store like with like. Creating copies of artwork is far more frowned upon by the people who initially stored them in the bank, though, so this merely has a clerk who keeps the vault organized and tidy. Because deposits and withdrawals are far more rare, this one is not at the surface, but rather the next level down from where the book vault is.

Currency Storage (1ss)

This is where mass quantities of trade goods are stored. Anything with a relatively fixed market price that doesn't rot can be found here. Precious metals, gemstones, silk and linens, even expensive materials components in some cases. Whether local merchants or traveling ones, the bank is always willing to store your valuable goods for a modest fee. This vault is near the surface, at the same level as the book storage.

Archival Storage (2ss)

This warehouse lies a level below the art storage. It is miscellaneous storage for objects that are to be handled with care, thoroughly protected, and not removed frequently. Generally this is museum pieces and nonmagical historical relics, but there are plenty of magic items to be found here as well. Why they are stored here long-term instead of used is for their owners (usually the state) to decide.

Curse Storage (2ss)

The world is full of awful people who make the world worse for each other. Whether they are being pawned, inherited, or have been seized by the government, many magic items bear curses on them, some more dangerous than others. The destruction of magic items is generally seen as a dangerous and wasteful prospect, but there is very little of actual value in these items except to keep them away from people they might harm in the meantime. They are removed very rarely, when a mage of some repute wishes to experiment with one and has received government approval to do so. It is on the same level as archival storage, for similar reasons.

Secret Storage (1ss)

This storage space does not appear on any blueprint and only the adventurers running the guild are aware of it. What's down here? The short answer is "a plot hook". The banking guild has been asked to lock something up using a vault as a prison cell, and they've done their best. Your choice on what it is and how it's locked up. This is one level below Archival/Curse storage and is difficult to learn about let alone access.



We also need to know how many ss there are per level since there's a surcharge for digging too deep. There's no surcharge for floors 0-2 (basement, ground floor, second floor). The others cost more:

Floor 2: 10ss
Floor 1: 10ss
Floor 0: 40ss
Floor -1: 35ss x 400 gp = 14000 gp
Floor -2: 30ss x 1000 gp = 30000 gp
Floor -3: 25ss x 2000 gp = 50000 gp
Floor -4: 1ss x 3000 gp = 3000 gp
Total 97000 gp



A space with 151ss is 70% interior walls and 30% exterior walls. This doesn't matter to me personally, because I'm making all the walls the exact same:

Obdurium: 60000 gp/ss
Magically-Treated: +18000 gp/ss

Total Wall Cost: 11,778,000 gp


Doors only go up to iron but that's not good enough for me. We'll have to bend the rules a little bit. Freestanding Iron Wall is 10 ft x 10 ft x 0.5 ft, or 50 cubic feet of material for 600 gp, or approximately 12 gp/ft3. An iron door is 7 ft x 3 ft x 1/6 ft, or 3.5 cubic ft for 500 gp, or 142.857 gp/ft3. If we're willing to round up a bit to make the math better for hypothetical walls, going from Wall to Door multiplies the gp/ft3 by 12.

A freestanding obdurium wall is 50 cubic ft for 6000 gp, or approximately 120 gp/ft3. Applying "magically treated" to it costs 12000 gp for every 800 square feet of wall face. As the single obdurium wall is 100 square feet of surface area, it will be 1/8th that price, or 1500 gp for the single section of wall, or approximately 30 gp/ft3. Together that's 150 gp/ft3 for magically-treated obdurium freestanding wall. x12 would make it 1800 gp/ft3 for a magically-treated obdurium door, for a total of 6300 gp per door.

Naturally, we shall have all the doors made like this. 1,902,600 gp in total.

Oh yeah and lets do two portcullises per vault. 20 of those. They're 1.5x whatever the door would be that's made of the same material. Magically-treated obdurium portcullises, ofc. 9450 gp per, for a total of 189000 gp.

There will be no windows. Live in the dark like a real dwarf. Due to recent diversity training, eternal light sources will be provided.


Naturally, amazing adamantine locks on basically everything. 1500 gp per, total of 483000 gp. The locks are now the easiest thing in this building to break...and in an E6 world, they're still damn near indestructible. Don't lose your keyring, the paperwork is a bitch.


We've finally arrived at the staff. Here's what we're looking at:

(12) Adventurer
(42) Clerk
(12) Cook
(2) Librarian
(6) Maid
(94) Military Officer
(6) Scribe
(14) Servant
(12) Valet

The adventurers are in charge of the guild, and have various capabilities. We'll have them as lvl 6, which means starting gear is 5600 gp.

Adventurer: 12 x 5600 = 67200 gp
Military Officer: 94 x 237 = 22278 gp
Total 89478 gp

And then let's have five years of wages up front, call it a signing bonus for the people cool enough to work at the guild headquarters for the whole country or whatever.

Adventurer: 60 x 12 x 30 = 21600 gp
Clerk: 60 x 42 x 12 = 30240 gp
Cook: 60 x 12 x 3 = 2160 gp
Librarian: 60 x 2 x 12 = 1440 gp
Maid: 60 x 6 x 3 = 1080 gp
Military Officer: 60 x 94 x 18 = 101520 gp
Scribe: 60 x 6 x 9 = 3240 gp
Servant: 60 x 14 x 3 = 2520 gp
Valet: 60 x 12 x 6 = 4320 gp
Total 168120 gp



Improved Arcane Locks on all vault doors (2 doors and 2 portcullises per vault, so 4 per vault, so 40). 40 x 175 = 7000 gp

500 everburning torches (the magic item, not the spell on a regular torch) at 90 gp each will cost 45000 gp

After the 1.15 multiplier on everything from our location, the total cost so far is 18,480,727.7 gp. Assuming a similar "40% of Ready Cash for bank defenses" as we had for the Large Town version, and taking the multiplier into account, you could buy magic traps and wondrous architecture with sticker prices up to 59,060,236 gp in total before we're going too far (by an arbitrary definition of "too far" anyway).

[Telonius]

The bank consists of a lobby, where the tellers do most of the basic business; and a vault where a decent amount of gold is stored for day-to-day operations, loans, and so on. The high-security deposit boxes are handled separately, and are very expensive to rent. The customer is led down a hallway filled with doors. They stop, ask you to present your key, and open the door.

The door is actually a resetting trap of Plane Shift, specially made to trigger if someone opens the door while holding the key. (The other doors are fake - they don't open to anything). The portal stays open as long as the door does. (Minor homebrew there). Try to open the door without the key, and the trap doesn't function; you open to a blank wall.

For each "security deposit," a unique demiplane is created by a member of the Planeshifter prestige class. Upon creation, the Planeshifter decides (as ruler of the demiplane) to prevent any Gate spell from accessing it. Each demiplane is about the size of a closet (though can be larger if the client needs it). When it's finished, the Planeshifter creates a tuning fork (the "key"), making sure it counts as an expensive material component (thus not available to a standard component pouch). The bank installs a small room that looks like a safety deposit box (since the demiplane can't have constructions on creation). When that's done, the Planeshifter leaves, and they close the door. Since there are no active portals to the demiplane, can start on the next one. As an extra security measure, a bank employee uses a Modify Memory spell to erase the knowledge of the key's composition.

Depending on how much security theater you want to include, you could have people approach blindfolded, go through a labyrinth, have an illusion of a door number specific to each customer, have an Antimagic Field in the room affecting everything up to the trap, or whatever else they can think of.

Care for the key is left up to the customer, and the bank takes no responsibility for a key being lost, stolen, or destroyed. They're paid when the account is created, and don't care after that. As long as you have the key, you can walk in and access whatever's in the storage area. If you don't have the key, you simply can't access the demiplane.

Alternate possibility: The customer doesn't even go back to get the contents, the bank employee does; so nothing at all is known about the security measures. (You could apply any of the standard anti-snooping spells on the trap room in that event).

[Inevitability]

For each "security deposit," a unique demiplane is created by a member of the Planeshifter prestige class.

I feel like you missed the E6 tag in the title...

[rel]

Even with e6, the enterprising thief has options.
- tunneling in with a pet monster with burrowing
- teleporting in with a pet monster or esoteric build trick
- becoming intangible (or less tangible) in some way and slipping past the walls
- applying social combat
- deploying brute strength
- sneaky rogue tricks

All that said, a sturdy vault and some competent staff with solid procedures can stop an awful lot.
You'd be amazed how many PC heist plans are thwarted by the bank having an ironclad rule that any large transaction requires 24 hours to process, so the bank can independently verify that you haven't been impersonated or mind controlled.

It's E6 so stick to mundane solutions as much as possible:
Put your vault on an upper story to discourage burrowing, require customers provide a key or similar so they can't just bluff their way in, put in some anti stealth options like beaded curtains watched by guards, maybe add some features that change the appearance of the vault or just fill the space inside it when the door is closed to foul teleports.

You're probably not stopping the level 6 master thief unless you're a level 6 master guard, but you should at least be able to stop the level 2 con artist with maxed bluff and forgery, or the monster tamer with a rust monster in a crate.

[Maat Mons]

Lining the vault with sheets of metal would stop most forms of burrowing.
Teleporting doesn’t require any build tricks. Dimension Leap is a 2nd-level spell.
Intangibility can partly be foiled by walls more than 5 feet thick. But unfortunately, the need for a door still leaves a point of vulnerability.

[Anthrowhale]

Dimension Leap is a 2nd-level spell.
Another good one.

Dimension Leap is 10'/caster level instantaneous.
Permeable Form is 1 round incorporeality, although potentially persistable via Illumian Cleric 1/Wizard 5.
Gaseous Form is 2 min/caster level with a move of 10'/round through any opening.

Dimension Leap is defeated by something like Rope Trick. Permeable Form might be defeated by Wall of Ectoplasm. Gaseous Form is defeatable with good engineering.

[JNAProductions]

Another good one.

Dimension Leap is 10'/caster level instantaneous.
Permeable Form is 1 round incorporeality, although potentially persistable via Illumian Cleric 1/Wizard 5.
Gaseous Form is 2 min/caster level with a move of 10'/round through any opening.

Dimension Leap is defeated by something like Rope Trick. Permeable Form might be defeated by Wall of Ectoplasm. Gaseous Form is defeatable with good engineering.

Quick question:

Dimension Leap let's you carry up to your capacity, I'd assume.
Would either Form do the same? Like, it's one thing to get in... How do you get out?

[Rebel7284]

No vault is impenetrable. Therefore, if you want proper risk management, you want to divide your items into multiple vaults. What sort of defenses you can create really depends on what level of magic you can get. Jaunter with the right cheese can get Plane Shift in E6. Is Plane Shift accessible? Etc.

[Anthrowhale]

Quick question:

Dimension Leap let's you carry up to your capacity, I'd assume.
Would either Form do the same? Like, it's one thing to get in... How do you get out?

Presumably, the limit is what you carry when you cast.

Incidentally, Hengeyokai[Sparrow] is pretty close to what Gaseous Form can do, but it's available at level 1.