AZ was recommended to me when I was looking but a quick trip to Craigslist showed that there were more RV's listed in Seattle than in all of AZ. Also RVs from hot places like AZ tend to have a lot more sun damage on them. I was told the stories of sunbirds who gave up RVing but those folks are few and far between, even in AZ.
We looked for 2 years for our current RV and finally found it from a private owner a short ferry ride from our home. We traveled several times to look at promising RVs that were a disappointment when viewed in person. My recommendation would be to limit your search to where you can drive and see potential RVs. It is a huge waste of time and money driving or flying long distances to see used RVs especially older used RVs. Pictures never tell the full story and sellers often have rose colored glasses on that don't allow them to see the flaws of their unit. After a prospective RV passes your thorough exam, then hire a professional to do a complete house and chassis inspection. It is money well spent.