I'd say the two biggest things to look out for are one, rust and two, pink milkshake. These frames seem to be pretty susceptible to rust, so I'd get one that's clean. You're in AZ, so that shouldn't be an issue, but just beware of it. The pink milkshake seems to be a bit more of an issue in areas where the temps can rise to a pretty high level. Just do a search for it and plenty of info will come up. Also, keep an eye out on your lower ball joints. Make sure they're in good nick.