"Fat" as in most things is subjective. Mine was an extra hundred bucks. I just spent 40 of that. I had put the books in the shopping cart back in July. I finally had some extra cash to buy them with.
Amazon used books are funny, you can buy a lot of different books for 01 cents. But they tack on 3.49 for shipping. Still not bad at todays prices for a book.
I sold some of mine last year on Amazon but it was tough making any money doing so. If it sold for 1 cent and then I had to pay A's fees and shipping I lost money. So I wound up only selling a few of my older s. King books for 10 plus bucks each. I made a little off of those. Not worth my time.