Mark was available, careful, and professional from the beginning. He took time to explain his business and the system. This was complex work, so there was some back-and-forth during the bidding process. Mark took time to understand what I was looking for and adjust his bid accordingly. In particular, our house was on the edge between needing a "3 ton" or a "4 ton" capacity unit. Some of the contractors I got bids from were either very confident that 3 ton was perfectly adequate, or certain that 4 tons was needed. Mark initially thought a 4 ton system was needed, but when I discussed this with him and showed him our low heating bills, we concluded that 3 tons would suffice. The system has only been "live" 3 days now, but already it looks like that was a good decision. The first part of this work was well drilling for the loop field. Here Mark relied on a sub-contractor, Bruce Walker of Wisconsin Well and Water. Bruce was great, although he had some equipment troubles and was not able to start when we had hoped. I give Mark credit for choosing Bruce for the drilling, and also for keeping me well informed as things came up and we had to push back the start date. Once the wells were done, the back hoe came for trenching. At this point there were a couple big ponds of wet well mud in the yard. Mark was able to get a truck come to "vacuum" these up so work could proceed. Mark himself did the inside work with a couple assistants (Cary and Justin) and an electrician. From all I can tell it is very good quality work. Mark makes a point to insulate hot/cold lines thoroughly and even to attach directional arrows showing how the fluids flow. There was something at one point that didn't read quite right with the compressor, and Mark got help from WaterFurnace (the manufacturer) to clarify. This installation allows us to heat, cool, and get hot water for our house very efficiently, using electricity rather than natural gas. Since we get the electricity from the We Energies "Energy for Tomorrow" program, I consider that we have cut our CO2 emissions by 6,000 pounds per year. I am very grateful for the help of Professional Geothermal in making this happen for a good price (his was the low bid), and with excellent quality and communication. More info and pictures of this work are available under "blog" at http://greenneighbor.org.