NEED TARP SIZE RECOMMENDATION!

We did have someone clean it and recaulk it around the edges in the past month (before he found a tear that he also filled in - this WHOLE process has been a big pain in our behinds. Bought trailer from someone we trusted last fall & parked it for winter. Didn't use tarp or cover bc we were following what local rv retailer told us to do. Found damage this spring when we opened it up. Brought trailer to a local rv retailer asap & they didn't even look at the outer roof - they just told us it was totaled. We had put a claim in on our insurance in the spring when we found the damage - they wouldn't cover it. We used it as is this past summer & figured we'd reseal/recaulk it & brought it to a buddy that worked in the service dept at another local rv retailer & he DID find a tear that had probably been there the whole time, so we put in a new claim on our insurance & they still wouldn't cover anything. So now we're stuck with this thing & we just bought it last fall & have no clue what to do with it bc we're first timers. The outside & inside of this trailer is beautiful, but we can't afford to fix it). Isn't there some type of sealing that you can "paint" on basically? (Excuse my ignorance - we don't know a lot about big trailers yet). I would be willing to do that to it, but I didn't know if that would be wasting our money, too since there is already the existing damage. UGH! hehe. Trying to create family memories bit me in the butt big-time ;)