I use Gel Gloss heavy duty
. There is regular Gel Gloss
, but the Heavy Duty version has a added UV protestors. I use regular on most of my exterior, and the more pricey HD on the decals.
A half gallon jug lasts me 5 years. I'll do a complete wax about 3 times a year. Each time I was the RV trailer, I'll wax one section (1/2 a side) or maybe the nose cap. Gel Gloss is both a cleaner and a wax in one. Been using the product for almost 20 years.
Most RV and Camping World stores sell it. I have bought some on Amazon too.
If you were going to buy I would get the HD formula. I think it's like $18 a 1/2 gallon at Camp World.
I take white terry cloth shop rags, put a 2" dollup on, rub it in over about a 3' square section at a time. Using the white rag you can see the grim it is taking off. Let it haze / dry for about 15-30 minutes, and wipe off with a clean soft rag.