Sealing up the roof permanently with ETERNABOND. We have used this on RV's, trailers and our home. This stuff works amazing and I can confirm we have never had a leak on any seam where ETERNABOND was used. See sizes below which can be found on Amazon!
Eternabond
2" by 50' https://amzn.to/38Vtzgn
4" by 50' https://amzn.to/3bZDzY7
5" by 50' https://amzn.to/3vF74WP
6" by 10' https://amzn.to/3lqGI6k
12" by 10' https://amzn.to/3vE5jJx