Not sure if possible, but hey I try?
Make it so you can push a button and see how much stock there is / how much empty space there is in a chest.
Like if I'm selling cobblestone, it will say I have 6 stacks of cobble left in my chest. If I'm buying cobble, it'll say I have enough room for 6 more stacks.
This is so I don't have to warp constantly back and forth between my storage and the shop, and I can just see if there's room in the cobble chest or not.
