Selling Used Books

I have a collection of around 7-800 books. I’m currently setting up an Amazon seller account so books under a certain value will be sold via FBA. For books over a certain value I’m trying to choose a different website to sell on (or use FBM).
Any recommendations?
Abebooks seems ok for sales but manually intensive to list on. Is biblio as popular?

Let us know how your experience goes. thank you.