I must protest painting with a huge brush. There must be more than one more excellent combo electrical/plumbing/heating contractor like the one that took care of my dad's house from the time dad was fully competent to the time his dementia forced him out. Contractor lives and and is based in a town of 2000, licensed in two trades for decades and is a very smart and even-keeled guy. I spent time with him on official school boy basketball courts. His biggest problem was always that he could not find employees who could perform at a small fraction of his standards so he was usually working alone. I can't say he never had a call-back, but it is difficult to get him to call at all because everyone prefers him to the competition. In addition to jobs dozens of miles away, inherently due to the rural location, I know that he sometimes works big jobs that are hundreds of miles away if they are of particular interest to him so he gets referrals far and wide. He deals with residential and big farms all the time and the latter are often more than not like dealing with industrial these days. On any particular day he is comfortable talking about a sizable three phase stand-by genset install with big underground propane storage that he installs on a property where he installed a septic system. On another day, in July, he might be dealing with customers on municipal water and sewage service, but he working on convincing them that they really need to replace that 50 year-old boiler before snow begins to fly. He really does not want to find time to fix their frozen pipes next January.