My experience is that a lot of them are auction based buys (like the Prestige Auto Gallery, which I would stay away from) and a lot of them don't have good reviews. (Example: Some say the car had major issues right after buying)

If you are looking at NYC area, stick with EMG, deluxe auto if you aren't looking at bigger dealerships. Just check out the car's history as well. Lot's of shady dealerships in Queens/Brooklyn/Bronx that have older luxury cars and they say they finance anyone.