EBay, Collectors, Flea Market & Antiques

you are unlikely to make much either way. I am amazed at the number of people who list good quality books online for a dollar or less..not worth the time it takes to list them. Used book dealers are not going to pay much either unless they know there is reasonable demand at a very good price.

If you have relatively few books, then amazon is definitely your best choice because they do not charge a monthly fee. In general, you can get more selling on amazon than ebay, although I check both sites since some books are "hot" on ebay. Alibris and ABE are both good sites but charge a monthly fee so unless you have a large volume the fees will eat you alive.

Good luck!