I live in North Scottsdale. My garage door is insulated and other than the door, only a small section of wall is an outside wall (two of the four walls are into living spaces). In the hottest summer days, my garage tends to run in the 90s and I have never had a problem charging at those temperatures. Put differently, my cars have always charged in my garage.
If you haven't done so, I would make sure your garage door is insulated and if you can insulate your garage, that would be helpful. Also, are you going to have an electric or gas hot water system. If you are going to have an electric system, consider using a heat pump hot water heater. It will reduce your electricity usage and slightly cool the garage (a heat pump, of course, moves heat but doesn't create it).
Being new construction, and given the way usage is moving, I would recommend a 400 amp service and 100 amps going into your garage. I have 225 amps but would prefer 400 but didn't want to trench my lawn to get the second line to the house.