Ex-library Books Good Choice for Resale

One place to find books for resale is at Friends of the Library book sales. Most libraries have these sales once or twice a year. Books for sale are usually books that have been donated to the library but because they are duplicates or have not been checked out in some time, they may be discarded by the librarians. Not all of these books are ex-library books (books that have been processed in as library books and have stamps and pockets pasted in to the front or back). Some of the books are like new, don't have library markings, and most libraries don't differentiate but sell all books for one price. Certainly the like new or very good books without library markings are worth a good look but don't overlook the older ex-library books.
Some books are designated from the printer as bound for libraries and these have a thicker, heavier duty cover. With a little experience, it is easy to pick out the ones designated as library binding.
Recently I sold an ex-library book. The topic was how to build a child's car at home and the sales price was $30. I was happy with this sale. Those booksellers who don't agree to sell books at a lower margin of profit would not have given this book a second glance as they would have felt it was not worth their time.
Often times the better books are the ones that were originally designated as library and therefore more likely to sell if a seller is willing to take a lower profit on books they resell.