I suspect that Kelly's and Edmunds' are accurate in terms of defining a mean average. However, the breadth of each standard deviation is understandably greater for limited production/special purpose cars than for full production vehicles, like minivans. With respect to the former, buyer peculiarities and special interests may well take precedence over established market values (you know, the red mist that descends on anyone buying his or her "dream"). I wish the seller well; but unless he finds a "dreamer" with funds, he may well be subject to the strict discipline of the market and the cruel scrutiny of an unflappable buyer. Of course, I could be wrong...