[blueskittle]

Another factor, related to bad data, would be price fraud. Fraudsters deliberately price a "vehicle" low (relative to mileage) in order to attract a high number of people. They know that only a small percentage will take the bait and send cash up front for a vehicle that he doesn't intend to sell, so he wants to make sure to get the highest number of people to respond to the listing. It's a classic buyer-beware scenario, so just keep that in mind as you see good deals in the "better" zone.