These RV's appear daunting to do but really are not that bad. I apply the Collinite with a DA and it goes pretty quick. As davidc mentioned, this is a project that will take a couple or a few days depending on how you want to work. And with trailers you will have to split it up so as to always be working in the shade. The Optimum Spray Wax is one of those that has the UV inhibitors in the wax. That on top of the Collinite should allow you to get by for several months....I enjoy detailing, and doing the trailer is enjoyable, I don't view it as a chore, so long as I split it up over 2-3 days....mine is also 31 ft in length.
I can tell you that with the wax on it, when it does need a wash after getting wet road grime on it, it cleans up real easy.