I'm looking for used car prices for luxury cars (i.e., Ferrari, Porsche). Essentially I'd like (for any given Ferrari/Porsche car) the price it sold for, the miles it already came with at the time of its sale, and the year it was manufactured.
It seems simple enough to search for, but after scouring the internet, I couldn't find a straightforward solution to my inquiry. Is there a government agency that could perhaps supply this data?