On our last trip through Arizona I built up a sun screen to cover the outside of the trailer around the refrigerator. We have the older 5.0 'fridge which works OK up to 90-95F, above that it struggles. The sun screen is to help when the refridgerator side can't be kept in the shade. In Bullhead City AZ it was getting hot, and the site wasn't out of the sun, so I took an afternoon to build this.
I built a 3D "triangular" frame out of wooden dowel rods with eye screws in the ends. The ends were tied together with wire, and later zip ties. It was held to the trailer with suction cups.
Two links at each end form triangles, then two longer links hold these in position. I found sun shade material at ACE Hardware. It allows air to flow but blocks much of the solar. This I put over the frame using safety pins. Not elegent but it seems for work.
It holds up to at least some wind. It folds into a small, but long, package by taking a couple of corners apart.
I'll likely not improve on it, by cleaning up the cloth attachments, since it works as is. We didn't run into any more hot temps during the trip so not much testing. My initial use leads me to believe it works about as well as parking towards the shade. And that's about all one could expect from it. SUCCESS!