CarMax does not even deserve the one star. I'll break it down for you.

Did not have the greatest selection.

Over Taxed vehicle and had to send a refund check.

We asked about the tires and complained that they were too worn, but car max would not replace because they meet their "standards"

Gave me the wrong spare key.

Had trouble with the car starting only a few weeks after purchase.

Took in for service, but had to wait two days because of the wrong key.

I was in an accident trying to take them another key so the repairs could be completed sooner.

They replaced the battery, but didn't tighten the cables, so the next time I stopped someplace a stranger helped me hold them together to get it to start.

Took in for service yet again, replaced connection.

Still not sure if they had actually solved the initial problem.

Car tags arrived on same day I had been in for the repair, had asked if they were in and they said no. Called a few hours later saying they were in.

Hassled the co-owner when picking up the plates.

Totaled my car in an accident were new tires may have been able to prevent. Then lost my entire savings because we had over paid and the resale was much lower.

I'm not saying that this is all their fault, I as a consumer should of been more aware. I just needed a car fast and this is what I found, and I trusted CarMax, Something that I think no one should.
I now am once again searching for a car only this time I have no money left.

I suggest looking at every option, doing tons of research and going someplace other than CarMax. Also get gap insurance with any car you get. That is if you don't want to end up like me and loosing $4,500