The only thing keeping me from rating this a 5 was the experience with your sub-contractor. They were friendly and professional, but the use of a internal combustion engine in the basement of an old house resulted in dangerous levels of Co2 to build up in all three floors of my house and my neighbors house. The fire department was called by our neighbors and the fire department insisted that this type of work should only be done with electrical equipment or with DIRECT ventilation from the exhaust of the machine.
Billy was a very helpful and informative guy.
My own internet research.