Many consumers look on Craigslist.com.  You can find just about anything you might want, and a few things you really would not want to take home with you.  One of the busiest areas on craigslist.com is the auto and truck section.  I wouldn't want to guess the number of entry's that are made everyday, but it is staggering.

There are 3 auto sections.  all, dealer and private party.  According to Arizona statute 28-4301-35 a "used motor vehicle dealer" is defined as a person, other than a new motor vehicle dealer, who buys, sells, auctions, exchanges or offers or attempted to negotiate a sale or exchange of an interest in, or who is engaged in the selling, four or more used motor vehicle dealers in a contiguous twelve month period.  Used motor vehicle dealer does not include a wholesale motor vehicle auction dealer, or a public consignment auction dealer."

If you look at private party listings, copy a phone number from an ad and put it in the search bar.  I have seen as many as 15 cars listed with the same phone number at the same time.  If you apply the statute listed above to the person offering these cars, that person is considered to be a dealer by the State of Arizona.

If you want to take a chance, that is ok.  The car you are looking at may be a great one, but it also could be ready to fall apart.  Also I would make sure that I take someone else with me to help examine the car and make sure there are no serious issues.  Some of the newer transmissions can be $2000-3000 or more to rebuild.  The better thing to do would be to visit a used car dealership,at least you then know exactly where to go back to if you have a problem.  Also there is no such thing as an "as-is" sale of a car in Arizona, so if there are problems, you can work something out with the seller to get the car repaired or get your money refunded.