Cost of custom magic item with multiple powers

[Xavram5]

I thought the rule was, take the base price of the most expensive power, then take the second one and increase it by 50% and add to base.

But what about a 3rd power?

Take this example

start with Feather Step Slippers (2k)...add in Daredevil Softpaw Boots (1400, so 2100)...and then add in Boots of the Cat (1k, so 1500)...2000 + 2100 + 1500...5600 gp for that item.

Am I missing some rule here? Or is that correct?

[OmniMage]

Yeah. Thats how I'd do it. Most expensive feature at full price, with each extra feature costing 50% more.

[Anguish]

That's correct.

CRB page 553:
"If the item is one that occupies a specific place on a character’s body, the cost of adding any additional ability to that item increases by 50%."

That said, the way that rule set is crammed at the bottom of the page doesn't leave room for the full details that WotC produced for 3.5e. Those rules had the space to explain... your most expensive ability was the one that was counted at 100% value and any lower-priced ability had a 50% premium.

1,000gp cloak of resistance +1
4,000gp headband of charisma +2
25,000gp bracers of armor +5

Those would be combined as:
1.0x 25,000gp plus 1.5x 4,000gp plus 1.5x 1,000gp for a total of 32,500gp