This is how I handle wealth, generally.
At low levels (1 and 2) - every copper matters. You're just getting started. You are trying to outfit yourself with some basic equipment. I'll ask about rations, cold weather gear, etc...
At journeyman levels (3 and 4) - You've had your first big haul. You're setting your sights on obtaining some magical items. We're wasting time if you tell me about how many iron spikes you are buying. I tell PCs when they can buy mundane equipment, but do not check on it at all. It is handled privately by the player (unless I want to drop a story hook at the shop). We only talk about whether you have gear if it is unusual gear.
At heroic levels (5 to 10) - You're well known heroes. If you want a stapler, you can be assumed to get one. It isn't worth discussing at all. if a player is on a journey and says, "I wish I had ball bearings" I'll tell them to give me a wisdom check. If I like the result (low DC), I'll tell them that they had the foresight to buy them and that they can add them to their inventory. PCs should have wealth sufficient to buy a few uncommon or a singular rare magic item in addition to what they've found, and although I might make them work for it a bit, anything they want to buy in their price range is going to pop up somewhere, somehow. At worst, there will be someone that can make it for them. Mundane gear is assumed to be there - you've been around the block and know how to prepare.
At super heroic levels (11 to 16) - PCs will have access to one or more sellers that produce potions, scrolls, etc... on a regular basis. They'll be able to buy these things whenever they want. If they want something off the list on a regular basis, the NPC will add it to their lists. They'll be able to travel to the great markets of my universe (the Cities of Brass, Iron and Gold; as well as my Planescape/Sigil equivalent). There they can find anything - for the right price.
Legends (17+) - I tend to move the game to more abstract patterns. There may be several years of game time between sessions (at times). PCs can get almost anything outside of legendary items if they focus their downtime efforts on doing so. The PCs wealth will likely be very vast at this point, with access to revenue generating features (mines, magic shops, etc...) potentially in their possession.