I agree working on the camper is easy compared to boats. I have owned 4 fiberglass boat, over the years, and sailed many on trips of over 2,000 ocean miles. I have never worried that my camper would sink ( guess I'm very lucky in I haven't found any leaks
YET), and that was always a worry on ocean passages in sailboats. One trip I had about 6" of water over the top of the foor boards. Seems the electric bilge pump was back flowing back into the boat. Don't think I will have problems like that with the camper.
Good luck with your project, don't get discouraged.