The vast majority of people make a very stupid decision by selling to a dealer and not selling private party.
A lot of Americans become very low IQ in the context of any car related financial decisions. Off loading their vehicles is one of the classic examples of this. Do NOT sell to your dealer. Carvana is the only exception and only because you can easily offload messed up cars to them without disclosing it.
It depends. I've gotten good prices from CarMax before, but like the other responder said, you have to research.
The other thing is that it's not always low IQ, but many people value simplicity. Do I want to show a car, deal with cashiers check fraud, flakey people, etc... or do I want money literally right now? I've sold cars to CarMax and I've sold cars and boats privately. The private price I think I can get has to be considerably more than what I can get with zero hassle.
