Called out to complete a home care inspection. Upon inspecting the the homes plumbing system found that there were a few things needing attention. Hot side water stop valve for kitchen faucet was non-operational. Tankless water heater was installed four years ago and has yet to get a flush. Recommended to replace the water stop for the kitchen hot side and to do a tankless flush today. Homeowner agreed and work with started. Began by shutting off water to the home and draining the system. Once system was drained cut out old hot side water stop in kitchen and replace with new quarter turn water stop. Flushed tankless water heater with vinegar for one hour. After one hour flushed water through the tankless to flush out all of the vinegar. Once work was complete reintroduce water to the system and turn the water heater back on. Just at all work for leaks and functionality. Everything is working properly and there are no leaks. Gave the customer multiple solutions for whole home filtrati