Whizbang Dustyboots
Gnometown Hero
Blue Rose does something similar. For most 5E games, after Tier 1, just abstracting character wealth to a not-particularly-granular wealth stat is fine.I always liked D20 Modern’s wealth stat.
Instead of paying for every inn, pint of beer and quiver of arrows you are assumed to be able to live at an appropriate level for your wealth. With a chance to requisition special, or expensive one off items depending on your wealth level.
Major treasures would increase your wealth for a certain number of levels for a certain duration or permanently for exceptional hoards.
I think it’s an interesting concept.