carbonel

Unless you recognize one of them, the third-party sellers are not a good indicator. At least some of them scrape book data from other sites, and put everything up for sale - and when you order one of the books they don't have in stock, they go buy it from someone else, and then ship it to you. This is also part of the reason why you sometimes see ridiculous prices on some uncommon books - site a lists the book for $20, site b scrapes it and lists it for $25, site c scrapes site b, adding more to the price. Somewhere in here, site a sees someone listing it for twice their price, and raises it, which then propagates through.