Customer has high water bill. Installed ball valve on 1” water service enters in rear. I shut ball valve off Isolating interior to exterior. Leak is inside of building onn cold.side. Shut stops off for both bath toilets. And shut off stop to compressor for dental work. Still small leak. Ther is nothing else above ground left to leak. Leak is in one of the cold loops. Will need to continue leak detection. I would start in rear where water service enters. I would expose cold manifold. Cutting and capping loops to locate loop with leak. Will return on Friday the 21st after 1:00 pm.