If you are asking about covering a painted Airstream Interstate motorhome, you can get covers from places like Camping World.
If you are asking about covering your trailer, it is not a good idea, because the cover will move in the wind, abrading the clearcoat.
I have gotten a couple of rolls of reflective foil insulation (like found for automobile windshields), and cut it to fit the windows. It rolls up when we want to see out, and stows in a storage locker.
Meddle not in the affairs of dragons, for you are crunchy, and taste good with ketchup.