My wife found a 2019 Surburban she likes and is going to go check it out. Assuming we want to buy it, how does Carmax work? I've bought used cars from dealerships before by emailing them about specific cars, getting their prices and going back and forth to arrive at a price and extras etc. Does Carmax haggle/negotiate, or is their price set? And if negotiations are to occur, is it any different than regular dealerships? Do they finance? We have a minivan that we'll be trading in — its so hammered I would probably sell it to Carmax even if we were buying our new car elsewhere.

Any tips are appreciated.