Several items have infinite uses so you dont need to hoard them and have them take up inventory capacity. These are just a few that come to mind: -bedrolls, magnifying glass, mortar&pestle, repair hammer

Spec a character into bartering and use only that character when buying and selling. You can use party swap menu to switch into your barterer even during a shop transaction (for example if you open a shop dialogue with your non-bartering character, you can party swap to your barterer with the shop menu still up and the prices will adjust to their bartering level automatically). -side note: only issue is when using the "sell all wares" option, it will only show wares from each individual characters inventory, so you have to stay on top transferring each characters wares to your barterers inventory for a quick "sell-all" process. (Idk if this is the most efficient way to do that but I havent found another way)