List the book for sale – If it looks worth your while to sell the book, head over to your seller account and get it listed. You can do a quick search here by title or ISBN to find the book. You will then be asked about the condition of the book, how many you have available, how you will ship it (Amazon gives you a $3.99 shipping credit for each book) and how much you want to sell it for. You're probably going to want to go with the lowest listed price if you want to sell your item quickly. People wanting to purchase used books want them as cheap as possible.
Peter, on the other hand, believes Amazon is where the big money is at. He is a high volume seller, however, earning over $130,000 in his first year as an Amazon FBA seller. Peter say’s, Amazon isn't just the biggest bookstore in the world anymore, it's the biggest store – period. The truth is that I have never met anyone selling books online who makes money anywhere except Amazon. It's where the book buyers are, and where the money is.”

When I was doing FBM, I was spending about 3-4 hours per night. Once I switch to FBA that went down to 3-4 hours per week, most of which was spending time finding deals on wholesale books and listing the books on Amazon. I was working full time for most of that time, so I could only do so much with the book selling, but still made about $1000/month profit doing it as a side hustle. When I switched to OA, it got a lot easier, as I just created a list of “hot finds” and would look around for deals on those. It’s surprising how bad people are at pricing things on Ebay–of course, that’s a double edged sword, as they’re also terrible at getting the conditions right, so I end up spending a lot of time arguing over books with writing inside, stains, smells-like-smoke, etc. Amazon charges individual sellers 99 cents per item that sells, so it only makes sense to list items on which you'll make a worthwhile profit. You only can sell items that are already currently listed on Amazon, which, of course, includes tons of book titles, CDs and some vinyl — but may not include everything in the collection you're looking to unload.
I check the selling price of Go Set a Watchman, a hardcover book I paid full price for, but one that I honestly never want to see on my shelves again. BookScouter says that one (just one) of the websites they scan will buy my copy for $0.12. Harsh. I didn’t like it either, guys, but that’s like $0.25 less than what it probably cost to print the dang book. My paperback of To Kill a Mockingbird, on the other hand, will go to three different sites for as much as $0.75.