Hi, people are paying a LOT of money to have their trailers painted or re-gel-coated...the only reason to paint a gel coat is if it is seriously compromised. Otherwise that's kind of the gold standard for coatings.
The little foam rollers do a very nice job (watch out for tiny bubbles!) -- you can either "tip" by gently brushing over the surface of a rolled paint until all the tiny air bubbles are popped, or keep rolling gently until they're gone...it makes a pretty nice finish.
You can buy VERY expensive paint, or basic auto paint...people have painted these with Rustoleum enamel, various marine enamels, the rubberized "undercoating" or "truck bed lining" paints (Durabak has many lovely colors, that can be mixed to make thousands of possibilities). It takes about a gallon of paint and somewhat less primer to do a 13 - 16 foot trailer. I'd figure on one coat of primer and two of paint.
It is very labor intensive, and shouldn't be undertaken lightly. It's best if you pull out all windows
, take off all trim, all lights
, etc. and get that primer and paint under all the edges. You need to do a LOT of sanding, before and between coats, a lot of wiping down, and making sure the cottonwoods aren't "blowing" their fluff when you do this. If you can get it under cover, inside a garage or something, so much the better.
We refinished our 1973 amerigo
(from dark brown with flaws and nearly 80 patches) to rustoleum marine white just in time to avoid those cottonwoods and their airborn mess. (We did all the work outside, in our driveway, between rain and windstorms here in The Great North Wet, starting with one window area and moving on window by window, then filling in the areas between. It came out quite well, surprisingly so, to me.
Someday we'll post photos...
Oh, and instead of putting in the rubber window spline, that decorative trim that supposedly keeps the screws "dry" but hadn't, we carefully cleaned out and painted all the channels black, right over the screws and all. Funny how the paint sticks even to the butyl rubber sealant that oozes around the edges of the screws. And if it comes off, we can touch up easily.
photo is of the old paint job. ANY photo of a white amerigo
looks a lot like ours does now. Haven't gotten innovative...just enjoying the standard look for a while.