We should have a PhoenixGAF meet up.
I'm down in Tucson, but I would totally come.
OP, I know I'm going to echo what a lot of other people have said, but here it is anyway. I'm not going to tell you what to do, because I don't know. But here's some information about Southern Arizona. I'm in Tucson, (About two hours south of Phoenix,) so YMMV
-Yes, it's hotter than Hell here in the Summer. Here in Tucson it's been around 110 degrees for the high all week, and we're usually a little cooler than Phoenix. It gets hot around Early May, stays hot until around Halloween.
-You learn to adapt. You get the best A/C you can in your home and your car. During the summer, you try not to spend a lot of time outside unless it's early morning or mid/late evening, and you always have plenty of water on hand when you have to spend time outside.
-Either find a place with a swimming pool, or that's near one you can use.
-During the winter, the high temp will be around 70 degrees, and the low will be around 30-40. At least in my part of Arizona, we see snow every couple of years, but we tend to only get a decent snowfall (like enough for a snowball fight,) every 5-7 years.
-Does Phoenix have a decent Monsoon season? Here in Tucson, starting around the beginning of July, expect to see some crazy thunderstorms. We've got pyrotechnics covered. But here's the crazy part - it will rain like crazy for about an hour, and then the sun comes back out and it's back to being hot again. This (officially) lasts through September.
-Snowbirds. These are (usually) elderly folk who live in colder climates most of the year, but spend their winters in Southern Arizona, where winter doesn't really exist. Be prepared for traffic to get worse from November - March.
-That's all I can think of right now.