Portable Air Conditioner for Camper - Originally manufactured for dog houses. Most are mounting to the tong and are commonly used on teardrops. They are currently developing units for larger trailers. A little price.
Pre-Order Cool My Camper Air Conditioning - smallest/ most power light camper AC i've seen - could connect to main battery and run as van AC - might be cheaper/easier than installing a standard AC system - probably cheaper overall to just not be home during the day
You’ll Be Incredibly Surprised At How Cool This DIY Poor Mans Air Conditioner Will Keep Your Car, Camper, Tent, Or Room. Step By Step Instructions And Proof That It Works! | The Good SurvivalistThe Good Survivalist