I’ll jump in with my opinion (FWIW). I’m going to assume you have an EPDM (rubber) roof given the age of the coach. If so I think it can be patched after cutting out any damaged structure. Probably not dreadfully difficult depending on how bad the structural damage is but maybe not a DIY project either. Really, though, it must be done unless you want to sell at a deeply discounted price. Best of luck to you.
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