Creatig Custom Magic Items D&D 3.5e

[Torgarn]

Okay, so I understand that combining effects from 2 magic items you add 1 1/2 times the gold of the more expensive item to the cost, if I wanted to do this with three magic items though how would it work?

[McSmack]

IIRC, it doesn't matter how many things are already on the item, each additional thing costs x1.5. I don't have the PhB handy so I'm using prices from Pathfinder, but here's an example.

Let's say you have a Ring of Sustanence (2500g) You add a Ring of Protection +1 to it (2000g x1.5 = 3000g) Let's say you then want to add Jumping to it (2500g x1.5 = 3750g) So the total cost of the Ring of Jumping Sustanence Protection +1 is 2500+3000+3750 = 9250g.

If you're crafting these from scratch remember to use the most expensive ability first, otherwise it gets more expensive.
Ring of Invisibility + Protection +1 = 23,000g
Ring of Protection +1 + Invisibility = 32,000g