I had a great experience selling my 2018 Audi A6 to CarMax in LA, and would highly recommend them.
My 2018 A6 was getting long in the tooth, but in great condition and low 15k miles. Got an online offer for $29.4k from Carmax. This was a couple hundred higher than Vroom or Shift, and thousands higher than what Audi dealers were offering as a trade-in and what some brokers offered.
I went to the Carmax near LAX, and their inspection matched the full online offer. This was a relief b/c I had already gotten a new car and was worried about last-minute gamesmanship. I filled out the info accurately, but who knows if they would have tried to short-change me for minor dings or curb rash, etc.
Paperwork was easy b/c I owned the car outright. Waited an hour after handing them the keys and paperwork, which was a little annoying but not to bad. And walked out with a check.
I probably could have gotten more through a private sale, but just didn’t feel like dealing with that this time around. Wanted a quick and transition to get into a new lease and say goodbye to a beloved car. Probably the first car I really loved.