Response to both inquiries, I have a '91 Casita
that had stress cracks on the top. I purchased the white elastomeric roof paint
from Home Depot and Lowes and I painted the roof of my Casita
with it and I did several layers to really put it on thick with a roller, this has not only sealed up the stress cracks, but my trailer stays out in west texas on my deer lease and I know for a fact it has been through some really bad hail storms(according to the rancher some hail was nearly golf ball size where I keep it) and I have inspected the roof and have not seen any signs of damage from the hail. The stones were big enough to break the exterior plastic vent hood for the range, but no fiberglass roof damage at all. The elastomeric roof coating is recommended for sealing mobile homes,rv's roofs and some building roofs. This is not for everyone, because you have to be prepared to lose the smooth shiny fiberglass surface. When this product goes on it will dry to a matte finish, but it is really durable, as I did this three years ago and it really has held up well to the elements. I liked it so well, I painted the entire trailer with it. The gelcoat on my trailer was completely shot so I did not mind the matte white finish. I think I remember paying $15/gal for the product and used 3 gallons for the entire trailer.