RMP or ZEP is not a wax or polish. It is an acrylic floor finish with little or no UV protection. Did my motorhome 4 years ago. The side that doesn't get the sun while stored still looks like the day I first applied it. I had to strip and reapply the side that gets the afternoon sun this year because it was starting to peel. If you can store it where it does not get much direct sunlight, it should last a long time.
I wash it with dish detergent and use Awesome to remove the stubborn black streaks. I highly recommend it with the above exception about long exposure to direct sunlight.