The thing is, even with the GTO that sells for $100K+ on the auction block, it's not generally a run-of-the-mill vehicle. They restore specific VIN#s in order to command those prices, the ones with #'s matching and original paint colors/interior or rare options (A/C, FI, Ram-Air, etc.). You'd have to be specific about the aircraft you chose, and a run-of-the-mill 172 or M20 isn't it. You'd have to look at more specific aircraft (like Staggerwings, WACO, Beavers, etc) that could be a niche market for buyers. You might even be able to do it with certain Amphibs.