It's little more than a concept because so few piston GA sales happen under those highly specific conditions. Those conditions work fine for someone whose teenage kid wrecked their silver 2014 Honda Pilot EXL with around 60,000 miles who wants to find another one just like it. Go to carmax and there are 34 to choose from. Bonanza's aren't like that. Market value isn't a useful concept for piston GA.

I have to disagree. I am not sure where your information is coming from but I've found the data used by NAAA members to be accurate for pistons as well as turbine aircraft. Brokers and/or dealers selling a particular aircraft may not agree with the results which is another issue entirely but the NAAA also has members who are brokers and dealers who generally agree with the data in their day-to-day activities across a variety of piston makes and models.

Good luck.