Rhino is a company from San Diego. As I understand it, the Roof Rhino is not the same coating that is used for Bed Liners of trucks. (I could be wrong, but after watching how they apply it, pretty sure I'm correct that it is not the same.)
But why guest? Look up Rhino's phone, and call and ask for tech support for this specific product. If you like what you hear, then ask them to refer you to the nearest authorized applier.
We went the Bus-Kote route on our fiberglass roof. I also researched boating Deck Paints too, and know some RV'ers go that route.
The real key is in the quality of the prep work, and application. Prep work, prep work, prep work. If not done properly, even though it may look nice upon completion, problems with separation can occur.
Depending upon region, the ratio between Labor to Material Costs can be as high as 65-70% labor in some regions, down to 30-35% in other regions. If you are a do-it-yourselfer - that ration drops to 0%
Best to all, and good luck as you all research what roof topping to use,