Had an inspector for the insurance company come by a few years ago.
He found an effluence under the carpet in the basement.
It was basically just a stain that hadn't even leaked into the carpet.
There were some drainage issues due to the way the house was built and the neighbors cedars being close to the drain lines.
He wrote up that it was mould, and they we needed to get the mould removed.
Tried to hire companies to remove the mould. Each said there was no mould, but wouldn't sign off in case of liability.
Insurance eventually cancelled us. In the meantime we saved up for a basement reno.
Eventually, we had the outside of the basement dug out and repaired, then gutted the inside, removed the floor (some asbestos tile was found), redid the drains, included a sump pump, spray insulated the exterior walls, and put on mould resistant drywall and new carpeting.
Had to re-sign with the same insurance company, as no one else liked that we had our insurance cancelled.
A few years later, we switched to another insurance provider that was much less.
I'm not sure if the inspector was a contractor or in-house, but they refused to question his judgement and send another inspector.