You might have the A/C repairperson check the voltage at your site and at any site that might be empty to see if it is better especially if he/she is there late in the afternoon when everyone's A/C starts kicking into overdrive. Then you can request a different site. This would be a free solution and would beat buying a patio awning that might not be welcomed in an rv park. You could still invest in the Autoformer if you plan to be in Arizona next summer, but at least you could save the repairs made this year until it arrived.
In addition to the aftermarketers offering a breakaway switch which offers an alarm when the lanyard is pulled (in case some... person pulls the lanyard as a "joke"), it would be nice if Airstream or someone else offered a plug-in voltage monitor which audibly alarmed when it was unsafe to run the AC.
A well designed unit would take into account the start-up surges of your own unit, and momentary spikes in the campground's loops.
I have a theory that now that I've polished the trailer, it should actually be a few degrees cooler inside than before, due to all of the heat bouncing back off it with the reflection -- sorta like the space wrap they put on sattelites.
Can anyone else confirm?
The "space wraps" are made from very thin sheets of GOLD. Its primary use was and still is for the discharge of static electricity.
In the very earliest days, the static discharge was due to the buildup on the satellites passing thru solar winds and, the resulting discharge of static electricity was extremely destructive.
Also
To properly cool an objection in space, you need to rotate the object at a specified rate of turn so that no one side becomes unduly hotter than the other. Other tricks are employed by the Space Shuttle when its cargo bay doors are left open in the extend position to act as a cooling fins.