There's about a million options for this.
I used the McGuire's for a number of years on my 06, 1st the Paint Cleaner (red bottle), then the polish (also red bottle), then the Carnuba Wax. Dropped the polish step after a couple years. The last couple years I had the hybrid I went to their #50 one step Boat and RV Cleaner Wax. I use a dual action buffer with the McGuire's foam pads. As you are starting from scratch I'd do either the 3 or the 2 steps, depending how fussy you are. Once it's been done you can go to the one step if you do it once or twice a year.
Even with all the care I gave it the decals cracked and faded, but not terrible. It was a Starcraft 18SB. Problem with removing the decals, at least on cars, is that they usually leave a shadow in the gel coat that may not buff off. Try a small out of the way area first.
On my new trailer I'm trying this stuff.