Bladder Control - Natural 1.

I once figured out how, for I think it was 1000 gp, completely under the Pathfinder custom magic item creation rules, one could craft a perpetually self-cleaning diaper using only the Prestidigitation cantrip. I speculated on how this would change the diaper economy in a world, because while 1000gp might be a lot for a commoner family, it's well within the reach of much of the nobility, and merchant-class folk could save up and purchase one to be passed down from generation to generation. They'd be pretty widely available since any magic artisan in the world could make it, only requiring a common cantrip (and the item creation feat).

(And of course, they could be made in adult size for the adventurer who disdains use of chamber pots.)

(re-figured it out since I couldn't find my old notes)

When multiplying spell levels to determine value, 0-level spells are treated as 1/2 level.

Value for a "Use-activated or continuous" spell effect: Spell level * caster level * 2000gp. Since we're using a 0-level spell at caster level 1, this comes out to 1000gp. None of the footnotes multiplying this value based on the base duration of the spell apply, since Prestidigitation has a duration of 1 hour, not a number of rounds, 1 minute/level, 10 minutes/level, nor a 24-hour duration or greater.

Prestidigitation allows many effects, one of which is to "color, clean, or soil items in a 1-foot cube each round." So the continuous effect would be to clean the diaper immediately upon soiling. For a large adult, heavy soiling might exceed the 1-foot cube area, so a waterproof cover is recommended so a 6-second delay in cleaning different areas of the diaper doesn't result in leaks. "Any actual change to an object (beyond just moving, cleaning, or soiling it) persists only 1 hour." so cleaning the diaper is explicitly excluded from being temporary, and would be permanent.

So an adventurer wizard could craft a magic diaper for half the market value, 500gp. There might also be cursed versions... >:3

*Wahzard