AZ is too hot the heat kills the paint..
I have great success buying trucks\cars in the VA area, DC and south, and sometimes NC too. It depends how new\old you want to go. my last truck came from VA beach area, it was a 2004 with 300K miles on it, great great shape, I have had that truck for 3 maybe 4 years now. I am in central NY, so these areas are a 6-8 hour drive for me.
2 years ago I did get my son a 2002 duramax from southern CA (he bought the truck) with 360K miles on it, that truck was clean clean clean. the LA area is dry but also not too hot, so the paint was also in good shape. I flew to LA with a one way ticket, had a list of trucks to look at, looked at over 10 trucks, bought it, took it to a shop to do some maint on it, bought a trailer, drove to northern CA to pick up a 4000lb CNC machining center, put it on the trailer and drove home! A bit crazy but worked out well and my son loves the truck. I was very impressed with the duramax, pulled that 4000lb brick like nothing, even with 360k miles on it! I would do that again.
If I was going to AZ I would look in the northern, higher elevation parts of AZ that are not so blistering hot.