I was curious to know how gazelle.com calculates a price for each item they will buy from you. Gazelle is a business that instead of selling items it buys items from the consumer. My question is, for example: http://www.gazelle.com/sell-mp3-players/apple/ipod-nano/21922-Apple_iPod_Nano_4th_Generation_8GB how does Gazelle know that say you put fully functional, good condition, all cables/manual/etc., it gives you a price of $49 at which they will buy it from you, how do they figure out this price? Do they have an algorithm, same thing with the graph they have right below. Anyone know? Do they just put different price values for each set of strings (questions) answered. So if I put it is in excellent condition the price goes up..but is that done all manually? really would like to know the answer, thanks.