I've contacted Mike Golden for three separate tasks, with wildly varying degrees of satisfaction. 1. Install a new tankless water heater. He did a neat job, but was hard to contact, and didn't come with the right tools to do the job. After one or more trips to the hardware store for drill bits, new drill, plumbing fixtures, etc., the job was complete. He noted that the vendor's installation manual required a 3/4" gas line connection, but that Mike has had problems connecting that size line to home gas lines because of the size of pressure reducer valve on the outside of the house. Instead of doing what the manufacturer required, he installed a 1/2" line. We turned on all the hot water valves and the heater kept up with the demand, so he determined 3/4" pipe was not required, and called the job good. I wasn't completely happy with that assessment, but it seemed to do the job. 2. A year later I had a sewer water back up problem, and Mike and his helper were able to determine the problem was associated with roots that had invaded the septic pipe where the pipe met the tank. Mike did not have the right roto-rooter tool with him, and left for a few hours to round one up. When he came back, he and his helper were able to successfully clear the problem, and seemed to do the job alright, and cleaned up well. 3. 30 months after the tankless water heater installation was complete, the water heater failed. I called the heater's official factory certified plumber to troubleshoot it, and he refused to perform warranty work on it when he discovered Mike had incorrectly installed the heater. The second plumber (Summit) showed me where the heater's air intake and output pipes were not correctly installed per the manufacturer's requirements, which resulted in the intake pipe pulling in exhaust air from the output pipe. And he found that 1/2" gas line was used instead of the required 3/4" gas line, which causes problems with the unit having to work too hard, and resulted in component failure. He would not do any further investigation or warranty work (the parts warranty is 36 months on this unit) unless / until the existing installation problems were resolved. He offered to fix them for me, but I figured I'd have Golden correct the problem. I called up Mike and found two of his listed commercial phones were disconnected. I called his cell phone and left a message. I left numerous messages until he eventually called back. He said he'd broken his ankle and would be another week healing, but then would come out. I understood and waited 10 days before I called him back up. In the mean time I'm without reliable hot water for several weeks. I made a schedule with him to have him install 3/4" gas line instead of the 1/2" line, and he didn't keep the appointment. I missed work to be there to let him in. He did not notify me he had problems or conflicts. I called and called and kept getting his voice mail. Eventually I called from a new number and he picked up. We rescheduled and he came without the right supplies, and said he'd run to the hardware store and be back in 45 minutes. He never showed up again. Never; not that day, not the next week, and never called. Perhaps he died. I left numerous messages, without any call backs. It's as if he recognizes my phone number and screens them so my calls go to voice mail. If I call from a new cell or a different phone number I might get him to pick up. But I could not get him to fix his incorrect gas line install. Summit eventually came out and replaced the bad gas line for $500, and I fixed the problem heater intake and exhaust venting, so Summit could troubleshoot the water heater. It cost me $1500 to get the heater repaired, and took four visits by Summit to finally get all the problem parts replaced. In the mean time I was still without reliable hot water. Since Mike never called me back, and since I'm out $1500 for the service required to correct his incorrect installation, I conclude he is unreliable, and I won't do business with him again. My impression is that he's a nice guy, very easy going, but not prepared and not reliable. I cannot recommend you work with him. I'm disappointed--I worked with his father, who is an excellent and reliable gentlemen; I incorrectly assumed Mike would be a chip off the old block. For this to be satisfactorily resolved, Mike must reimburse me for the costs of replacing the gas line and for the service required to the heater as a result of using too small a gas line. I won't ask for the four days of lost work time I incurred so I could be home for the second plumber to do the additional diagnosis, troubleshooting, and parts replacement / repair, although I think that's a valid request.