When it comes to thermal imaging the FLIR name is the gold standard.  Used by the military and police for the most demanding applications, they are on their A game.  The technology is getting better and coming down in price which makes it available to the common folk.  The MR160 is basically a moisture meter that has a 80×60 thermal imager to pinpoint the exact source of the leak.

FLIR calls it IGM – Infrared Guided Measurement, it guides you to warmer and color areas on a surface.  This generally indicates moisture.  You can then use the included pin external pin probe or the pin-less method to get an exact reading.  The unit is capable of capturing the thermal images on the onboard storage.  You can create you own custom reports, with your logo to give to you clients with the free FLIR tools software.  It has  2 yer warranty and be charged via a USB port or the included USB charger.  This tool will pay for itself within your first few jobs.  The days or tearing things part to find leaks are over. The FLIR MR160 will save you time and money.  Your business will have the edge over the competition.   Check out the FLIR MR160 via Amazon.