Hello. Indeed water damage to a trailer is the most common concern expressed in this forum since I've been around. Various remedies to detect this kind of damage have been proposed such as visual and hands-on inspection, water meters etc. I sure would like to know what the readers of this forum have used proactvely to determine water damage and how it turned out. I ran across a company that promotes a device called the Seattech 430r which are found at various RV shops around the country. If you search engine that name you will see where the testing stations are. General RV in our area has one and when i called about it they said they are booked 3 weeks out and charge $150.00 for the test. Sir Lancelot in your area the closest test site is in Fife. I got all this stuff from their website. Good luch.