Option A is a no brainer - just give it a proper inspection. Those cars get maintained better than most other cars, so the mechanics and systems will most likely be in good order. Mistreatment is most likely to be cosmetic - dents, scratches, wear & tear on interior - the big one would be smoking. $12,000 is a lot of money.....
http://www.momentumaudi.net/certified-inventory/index.htm?year=2016&&&& I think they take these loaner cars when they get to around 5-8K miles and certify them...and sell them as CPO cars.
A concern would be does it take premium or regular gas? If premium, people probably didn't care if they put regular in since it is a loaner.
I just bought one of these last month, 2015 A6 2.0 w/ 4k miles. Was listed for 42k, only got about $300 off the price, those f'ers at Audi Central wouldn't budge on the used car prices. Also they have some anti theft fee they try to charge you, tell them to take that off. I couldn't get them to take off the $400 dealer fee. Good luck!
Ya they don't budge at all! Are you talking about the phantom fingerprints crap. I got that off and had them tint the car, and took 500 off. but of course the stupid dealer fee is there...
lookwise A7. otherwise they are both the same in terms of engine and platform. of course the a6 is much newer.
Not a car guy, but I don't see how even inconsiderate drivers can do a lot of damage to a car in under 5,000 miles.
Ima tell you what Ballers taught me... Never buy a depreciating asset. If it drives, flies or floats always lease!
Update: so I did end up buying that 2016 A6. Wife loved it much more than her BMW. and oh almost forgot...she drove it into flood water last week. car = totaled.