Enchant clarification

[Shnigda]

Hi everyone, I am fairly new to DnD (playing for just under a year, but only played 3.5 for 4 months or so) and I have a question about the prices for armour enchants.

I understand that a standard +1 item (longsword, chainmail etc...) costs 2000gp (+ masterwork item cost) and that a +2 item costs 8000gp. I also understand that to upgrade from a +1 to a +2 you pay the difference (so in that case you would pay 3000gp).

However, my question is about enchants that say the cost is equivalent to a +1 bonus. Does that mean that it costs 2000gp (equal to the cost of a standard +1 longsword/chainmail etc...) or does it mean that the cost is equivalent to taking it to the next enchantment level (from +1 to +2 (so 6000gp) or from +2 to +3 (so 10000gp) etc...)?

Also, if I wanted another +1 enchant on an item, such as a +1 flaming longsword (so there is the equivalent of 2 +1 enchants on it), what would the cost be?

(I realise that this is a bit garbled and possibly difficult to follow, but any help would be much appreciated)

EDIT: Prices

[OldTrees1]

You first calculate the effective bonus.
Ex: A +2 Flaming sword would cost the same as a +3 sword because flaming counts as a +1 to the total.

Then you find the price
Ex: A +3 sword costs (3^2)*2,000 = 18,000gp (remember weapons cost twice as much as armor/shields)

To find the upgrade price you subtract the existing market price from the upgraded version's market price
Ex: A +1 sword -> +1 flaming sword(costs same as a +2sword) would cost 8,000-2,000=6,000gp to upgrade

[Shnigda]

So when an enchant says the price is a+1 bonus, it means that the price is the cost it would be to take an item to the next enchant level? eg the price could be 6000gp to take it from a total of +1 enchants to a total of +2 enchants, or 10000gp to take it from a total of +2 enchants to a total of +3 enchants, and so on?

[Glimbur]

Yes, that's right. So it gets more expensive to put more and more enchantments on an item.

At some point someone will point out that you can cast Greater Magic Weapon (http://www.d20srd.org/srd/spells/magicWeaponGreater.htm) on a magic weapon, allowing you to spend more on other enchantments. But that's a start to how Wizards Cheat, and you might not want to go there yeat.

[Flickerdart]

I understand that a standard +1 item (longsword, chainmail etc...) costs 2000gp (+ masterwork item cost) and that a +2 item costs 8000gp. I also understand that to upgrade from a +1 to a +2 you pay the difference (so in that case you would pay 3000gp).
Actually armour is half the cost of weapons - 1000gp for +1, 4000gp for +2, and so on. You can also ease the load by putting half of your armour enchantments on your armour and half on your shield (at least, for those enchantments that can be put on shields) or wielding a double weapon and enchanting the end you don't use with enchantments that don't activate when you attack.

For example, let's say you wanted the Quickness and Light Fortification abilities, both +1. You could get them both on a suit of +1 leather armor for 9160gp, but a suit of +1 leather armor of quickness and a +1 buckler of light fortification is only 8325gp.