Water Dripping

I have noticed a steady drip of clean fresh water from the rear drivers side it drips off the rear valance cutaways for the steadies, but I cannot see any damp on the floor or where the leak is coming from, Marquis checked for damp (none) and could not find a leak (not sure how hard they looked) Left overnight it will leave 3 inches of water in a standard bucket. Water is clean and the drip is steady. I am loathe the remove any bathroom trim to investigate so failing any advice it will be a further trip to Marquis. Thanks in advance

Hi
I have sent you a P.M
Boaby