Also add a list that seperates all to categories like shotguns, swords, daggers, revolvers, clothes etc and when you first press the move all to inventory the list will show and you can decide what you want to keep or not and after that also add a message that asks you if you're sure you want to do it.
At first all categories will be selected and you can just remove whatever you want to keep from being selected.
In addition maybe make it possible to move quest items, weapons and clothes with levels to inventory.
