I prefer using my library. They usually have new releases that would be pretty expensive to buy and me utilizing their services helps the library to stay open and receive funding.

If I really enjoy a book I’ve read, I will add it to my buy list. I reread book that I enjoy often, so I only want to purchase books that I know I want to reread.

I actually do prefer buying most nonfiction books though, especially anything not a memoir or biography. I like to annotate and refer back.