Wow, if you found an A8, especially a C6 generation A8, for that price, I'd buy it on principal alone. Those are freaking NICE roomy cars, lol.
IF I decide to flip it, I'd probably ask like $8500 and settle for $7500-8000. Dealer asking prices with miles like that around here are in the $9-10K range still. I know I'm saving for that other car I want back but I just saw so much potential in this one that I couldn't pass it up. Gotta spend money to make money right?