While I am generally a fan of having characters gain experience based not only on the amount of enemies they defeat in battle but also on how many treasures they retrieved during the adventure, dealing with individual gold pieces always seemed too fiddly to me.
My preffered way to handle treasure both in regard to wealth and encumbrance is to use a simple unit of “1 treasure”. As long as characters still have 1 treasure, they can buy any items and services of trivial costs, such as food, drink, a room in an inn, most weapons, and so on. Anything that is too expensive for most common people to affort cost 1 treasure, such as a horse, chainmal armor, or a boat. As a rule of thumb, every treasure is worth about 100 gold pieces and can consists either of a bag of coins, a large golden cup, a crown, or whatever else the GM wants to describe it like. It also counts as 1 item for calculating encumbrance. (A character carrying items numbering up to their Strength score are unencumbred and can carry twice as much being lightly encumbred and three times as much being heavily encumbred.)
The treasure tables in the Basic and Expert sets of Dungeons & Dragons give various chances and amounts for different types of coins and gems, so using this alternative treasure system while retaining the same rate of experience gain requires some conversion work.
Which I did. Here’s the result.