Co leak upon arrival. Customer stated that AGL came out and found a co leak at the water heater. After looking at water heater noticed it was leaking, as well as an incorrect vent. Checked pressure and read it at 120 the building had two PRVs. Also noticed leak on 3/4 copper line and a fill valve in the basement toilet constantly spraying. Informed customer of all issues and the work that would need to be completed including 2 new PRVs, new gas line ran, new navien 240a2, running the vent outside, fixing the 3/4 copper leak and fixing the toilet. Gave customer estimate, customer approved estimate. Installed new navien 240, fixed leak, repaired copper line, and installed two new 1 inch PRVs. Turned water and gas on. Found no leaks on any gas lines inside the building and no leaks on water lines. Tested to make sure tankless was working properly. Tankless is working properly and no leaks found on any work we did. Customer has slow gas leak on the roof on a mega press union. HVAC company