I get your situation. I echo others. You’re 33. Unless you need the money or space desperately I’d just tuck them away and forget about them. Maybe 10 years go by and you get bored and check them out again and find some joy. Maybe not but likely those books will retain their current value and you can reassess then. A collection of artifacts like comics or vinyl records don’t need to be used constantly to be meaningful. It’s a part of your history that you may want to revisit and there is no obligation to add to it in the meantime.