With modern technology- moisture meters and infrared thermography- home inspectors can find water issues that aren’t visible with the naked eye.  This photograph shows underlying saturation adjacent a toilet that needs to be reset with a new wax ring.  Hopefully there isn’t underlying damage; they’ll find out when the toilet is pulled.  I use moisture meters to probe around toilets, showers, sinks, dishwashers, and any suspicious areas to confirm elevated moisture conditions.  It’s a valuable tool for sure.  This photograph was taken at a recent home inspection in Oak Harbor on Whidbey Island.