Although there will be books that you will want to keep, don’t forget that you can rent books for much cheaper for elective classes, etc… My kids (and I) have used Chegg and Amazon but there are other sites out there that rent books. It’s worth checking into. Another option for purchasing books is to hook up with a student who is ahead of you in the program and buy their books from them at the end of each semester. My son has had a number of older students offer to sell him their books because they don’t want to go through the hassle of trying to sell them back to the bookstore.