Ok, let me give you a real honest review of Carmax. They get two stars cause the guy I met with was awesome (wish I remembered his name).
Other then that ... Let me really tell you about carmax. They give you an appraisal (takes about 30 min) and they say they give you fair value after all marketing costs etc. ORLY?
My vehicle was going to get me 16k for a trade in at dealer across the street, and books at 18,100. Their offer? 12k. It's gonna cost 4-6k to market. I think not.
If you are looking to sell your car, go to craigslist, autotrader or ads or put a sticker on your window. You will get more money. Fair value? When even a dealership (normal one) offers me more. You know there's something wrong.
My 2 cents is all this is though ...
Oh yea and they will email you results. The info you give them will get you emailed and snail mailed ... Constantly. You have been warned.