I'm really sorry to read this.
I bought my first camper back in late 2016. After using it for about 18 months I noticed the cabover starting to droop. I opened it up and when I realized how much rot was in there that was the end of that camper.
A place who did that type of work gave me a bid of $6-7000 to redo both sides. The camper wasn't worth putting $6-7000 in to it.
I learned my lesson and bought another camper back in July 2019. This time I knew what to look for and a good friend with a lot of RV experience helped me with the inspection.
Good luck.
