Customer mentioned high water bill. Started test by isolating main water service line by shutting off inside shutoff and checking live meter. Meter was at a stand still indicating no leak in yard. Second test was marking all toilets fill line and shutting off toilets for 20 minutes to see if toilet tanks would lose any water. Once returned after 20 minutes all toilets were still full and none refilled once stop was turned back on. Double checked water heater as well. NO SIGNS OF ANY ACTIVE LEAKS IN HOME.