For my first ever post on this forum, I'll reveal a dark secret that I usually don't tell anyone, years ago I spent about a year in the used car business, yes I was a used car salesman! I was actually fairly good at it and made some decent money during that time, which isn't always easy for the new guys who don't have the benefit of repeat customers. It was a fun job at times, but the hours can be long and boring, especially on those weekdays waiting for hours on end for someone to pull on to the empty lot. I always aspired to have my own business, which is also what pulled me out of my time in the world of used car sales.
Anyway, my reason for revealing this secret is to tell everyone not to put all that much stock in what "the blue book" says a car's value is and that is especially so for anything rare like an Aston Martin or any classic car. Its hard enough to put an accurate value on a Taurus or Camry, cars that they sell hundreds of thousands of and are sold and resold many times every day, everywhere. How in the world anyone can publish what they think are the accurate values for a rare car like an Aston Martin, Ferrari, Lamborghini, etc or any particular classic car is beyond me. Furthermore, with any exotic the value can go up or down so much based on what kind of service history is provided. I'm new to Aston Martin's (hanging out here to get some info for a purchase in the near future) but when you take into account things like a Ferrari F1 transmission's clutch costing $10k+ to replace and that it goes through those clutches fairly often, there's a lot of play in such car's values.
Even for common cars, the book value should only be a very general guide, it all depends on what someone's willing to pay for your particular car at a given time and I'd say its far more true for any exotic!