Carlos gets top marks from me. He was fully knowledgeable and informative on the issue at hand. He was clear and understandable in his explanation. He explained what he would do before he did it. When I asked if I needed to be present in the home while he worked, or if I could depart, he said I could leave if I felt comfortable with it. He said he would pull the door shut and be sure it was locked when he left. I departed, then returned before the job was completed. Carlos gave me a complete explanation of what he had done, he explained options that I have for having my furnace and AC serviced each year, and he described a package deal that I could get if I bundled them together. He was a pleasure to work with, and I would welcome his service again at any time.