The tower is three levels. It is a Medium sized building - a smallish magetower, or a small vertical warehouse, depending on one's cynicism. In has several empty rooms on each floor; enough that all 6 characters can have a small room to themself (bed, and perhaps another two or three pieces of furniture.) This is Living Space for the PC's, but not for any NPCs you pick up, who will have to pitch tents in the yard, or else rent rooms in town and walk up to the guild hall each day until you build to accommodate them. There's a secret escape tunnel that leads from a hatch in the lowest floor , down a hundred yards of rope ladder, and then west south-east-east about two hundred yards through a lightless passage to a secret dock in a sea cave at the base of the cliff just south of ratchet proper. There's a crummy little wooden jetty there, enough to cast a fishing line from on relaxing evenings, and the cave has a high enough ceiling that a small sailship with a collapsable mast could row out to sea.

Aside from that, the deal you're getting gives you enough clout to have 3 BP worth of additional alterations done to the building. Obviously applicable ones are fair game (training room, infirmary, etc). Anachronistic ones I can be persuaded toward if you have an idea how it could work (Communication centre as a room dedicated to homing pigeons, racks of two-way magical communication stones, crackly gnomish radio, or what have you, for example.) Some just don't work, either at all or for now (Secret can't apply because this is a known installation. Dimensional Portal can't apply because creating a Dark Portal requires the massacre of thousands of Draenei and a demon-born madness. Teleport Lock can't apply yet because you'd need to be a little more in with the Kirin Tor for them to approve and set up a teleport circle in your guild hall.) Anything not on the list that makes sense can obviously be negotiated!
I posted! Thanks for your patience, guys. Above is a reminder of what I pitched to you guys when I first mentioned the tower. I believe Alchemy Lab, Library and Garden were the three most sought after picks, once home defense was considered covered with your staffers. Does that still hold? Any objections? Last chance. :)