On the second picture, I can see some gelcoat crazing. That's not normally a structural issue, it's just cosmetic. I can't tell on the others, but if the gelcoat has been rubbed out enough that it's starting to show the layup colors, it may be time for paint
, new gelcoat, etc.
My preferred solution for both problems is thin coats of Sherwin Williams best enamel paint
. De-wax, use a random orbital sander at 220 grit, use a tack cloth, then one of those cat's paws small foam rollers. Put the paint
on in very thin coats (to prevent bubbles) and you will have a long lasting finish that will make people think you have a new trailer.
The crazing might need a bit more prep. Glazing compound, bondo, etc. You don't want to leave the cracks open before covering them with a finish coat.
This technique worked on my Tanzer 22 sailboat for the five years I had it, with no discernable fading. And I kept that boat in the water, so it was a fairly harsh test.
All that, but fiberglass is rugged. You don't really need to do any of this if you don't have the inclination. It will just sit there and not do much of anything!