If you're going to do a third edition I would leave the value section out as others have suggested. Even if data from completed sales could be accumulated it would soon become outdated.
Not trying to ***** you off Jack, but if you do a third edition, do it with your eyes open. I really don't want to read for the next ten years at what great peril it was to write it, how many people ripped you off, and how newcomers to the hobby under appreciate your efforts. If it isn't going to be a labor of love then what's the point at this stage of the game.
Everyone on this site appreciates your effort and will support it by purchasing it. I have both pump books and the air meter book, they get a lot of use.
