Wow, that's very expensive. I'm not familiar with that product, but I find it very hard to believe it will last 4 years. Get you a can of Collinite 476s for less than 20 bucks, some elbow grease and save the money. If elbow grease is out of the question then pay someon 100 bucks to apply it. If you are worried about the interior use Scotch guard on the fabric, etc. We too used to have an RV in Florida and never had a problem with germs or odor. If you are worried about humidity there are products to take care of that...basically silica bags, pouches, cans.
2014 Forest River Georgetown 351DS
2014 Jeep Wrangler Unlimited Rubicon Toad