Organising a TF2 Inventory Before Buying New Items

My TF2 inventory has become a mixture of items for classes I play often and items I kept simply because I received them years ago. I want to buy a few skins for the classes I actually use, but I cannot tell which older items I would miss after an exchange. Selling everything that seems unnecessary would make the budget easier to calculate, yet it could also leave me regretting a quick decision. How would you sort the inventory before entering a marketplace? I need a practical plan that separates items I genuinely want to keep from things I have stopped noticing.

Make three groups: regular use, personal favourites, and items you are willing to part with. An item can deserve a place in the second group even if you rarely equip it, so do not let usage alone decide everything. Then list the replacements you want by class and set a limit on the total purchase. I would leave the first two groups untouched during an initial transaction. That gives you a smaller pool to work with and reduces the chance of adding a sentimental item to an offer just because it closes a small price gap. Review the plan again before sending anything out of your inventory.