Probably just like any car dealer. Say your car is appraised for 15,000. Suppose you owe 10,000. You pick out a new car for 17000. 17,000 less 15,000 is 2,000. Add sales tax dealer fees,DMV fees and your loan amount 10,000. Less any money down, this is what you would finance. Depending on the year of the car, 48,60, 72 months. Good luck. Car Max is good because everything will be explained to you. If they appraise your car, you tell them how much you owe, and how much you can put down, they can tell you what price car to look at.
CarMax will just give you another car you cannot afford. They wouldn't let me test drive a car as i only had a UK driving license as I'd just relocated with work and no permanent address means you cannot get one. However- they were more than happy to sell me one and if i didnt like it I could return it. Imagine that. It would not have been so bad but I'd test drove many cars at other dealers on the same day prior to arriving at CarMax. No problem. Avoid!
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