#40Fan wrote:
He covered the exterior roof?
Yes  he did   and it was amazing how well it worked.   If you were going to be in a place for a while  and it was  over 90 on a regular basis,  might be worth a shot.   When we had the RV with only 1 AC unit, we shut off the bedroom  had  reflective on all the windows and had reflective  on the sides of the slide outs that faced the sun  and we still couldn't get it cool enough.   We put a sheet over the front cap area also when we were in an area that was over 90.  
It is the roof that causes the heat, so  it makes sense.
He swore by it and  the inside of his unit was definitely cooler than ours.  
Might be worth a try.