I have about 10,000 volumes and I realize that I will never be able to afford the space to put them on shelves, these are real books, not Stephen King and science fiction stuff.
I would read and pack them away for some distant future but now I just can’t see ever being able to really use them again, I don’t know what I’m going to do with them. I could sell them on E-Bay but I don’t like the world of selling used stuff, and all the mechanics and effort of it.
Consider making them a donation to a good charity or foundation or organization.