Buying a used car is a bit of a crapshoot. What do you do to make sure you aren't getting swindled when making that big purchase.

One element that cannot be ignored is the pre-purchase inspection. You might be able to look at a car, especially an older classic, and say "oh, that's nice," but you probably don't know the intricacies. Getting a pro mechanic to look over the car makes all the difference.

What do you say? What's the one thing you have to do when buying a used car to make sure you don't get screwed?

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