We designed Maya’s tiny house to connect to utilities with standard RV connections. On the left is the water supply inlet and on the right is the 220V 50A electrical connector. Today was spent testing our water supply, drain and wiring before insulation and sheathing make it more difficult to address any issues. The test results: Wiring (PASS); Drain Lines (PASS), Water Supply Lines (FAIL). The water supply had two leaks.  The first from a PEX connection that I had inadvertently forgotten to crimp (dumb mistake but easily rectified in all of 30 seconds).  The second was from the factory supplied fitting at the outlet from the water heater. Even after tightening the compression fitting there was still a tiny leak.  I decided to replace both inlet and outlet fittings with new ones which meant a one hour trip to Home Depot. The new fittings addressed the problem and we kept the lines pressurized for another 2 hours to ensure we had caught everything.  The remainder of the day was devoted to completion of the branch wiring circuits. Maya installed most of the boxes, drilled holes for and pulled much of the wiring.