Is there a feat or ability out there that lets me use a magical item more than once. Feather step slippers are usable once per day for 10 minutes, for example. Is there anything out there that might get that up to, say, three times per day?
Shadow-Traced Creature template (3PP) lets a creature create temporary duplicates of itself as well as its gear. Any consumables the base creature possesses are therefore effectively infinite uses per day.
If an item doesn't have any kind of required attunement (i.e. "must be worn for ____ hours to take effect"), you can just buy multiples and change them out once you've used one pair's 1/day use. For that reason, I'll usually just let my players buy multiple charges for the same price as the first. Functionally it works out the same, roleplay-wise you don't have a character walking around with fifteen pairs of identical shoes and stopping after every fight to change them.
If an item doesn't have any kind of required attunement (i.e. "must be worn for ____ hours to take effect"), you can just buy multiples and change them out once you've used one pair's 1/day use. For that reason, I'll usually just let my players buy multiple charges for the same price as the first. Functionally it works out the same, roleplay-wise you don't have a character walking around with fifteen pairs of identical shoes and stopping after every fight to change them.
I had considered combining multiple instances of the same item (at a 50% markup for each one after the first), but I wanted to see if there was a pre-existing option out there first.