First, ask them fax you a copy carfax report. The dealer

can usualy give it to you for free.

Second, check the website of the dealer. Don't deal with them if they only have 10-20 cars.

Third, talk to them and ask specific questions. such as if there is any flood damage (though accident free). You can have a feel most time if they are honest from the way they talk.

If it sounds to good to be true, then it usualy is not true.
You want to buy a car that is a little bit below the average price to get a good deal. Don't expect to have a steal unless you are an expert.

You should also remember that many car got repaired by a private shop and may not be reported in carfax.

When large amount of money get involved, you may want to fly there to have a close look and then drive it back home.

With averything said and done, you are still taking a risk.