How to write a report when moisture is discovered in a crawl space during a home inspection?

I've encountered this pitfall before when entering a crawl space for a single-family home inspection: the wooden beams didn't show obvious rot, but the ground vapor barrier was damaged and the humidity was high. The buyer asked if a major repair was immediately necessary. At the time, if I had only addressed the most obvious surface issues, it might have passed in the short term, but it…