The Blue Book is designed for the use of Pawn Shops. In reality, there are only about 25 items in the Blue Book that have actually appreciated in price since first introduced. The Blue Book valuation of a piece of gear is nowhere near indicative of its value in the open market, it is designed to give pawn shops a benchmark on buying, selling, and what to loan money against ($ value). If anyone offered me "Blue Book" value for a quality piece of gear I was selling, I would throw them out on the street. I would expect to be treated the same if I tried it. The value of anything is whatever someone else will pay for it. Look at eBay, people are paying huge amounts of money for crap that wasn't even good when it was new. Put the words "rare" or "vintage" in the description and people start vomiting blood. The price goes up and up with no rationale except thet there is another guy who wants it more than you, so he bids higher. Wilson Watt Puppy 6's are so new that they will not appear in the Blue Book until the 2001 edition. I would expect to pay list less 15 to 20%, depending on how motivated the seller is.