I asked for a 12pm appointment. They wanted to give me 11:30 but agreed to 12. Glen arrived at 11:30 and insisted I let him in at that time. He snooped in my kitchen even though I tried to guide him to the furnace in the hallway. When I asked how long the tune up would take Glen told me "a few minutes". I was alarmed and asked why a $90 tune up would only take a few minutes. He rudely replied this tune up has only been $90 for 20 years any one who charges less will just try to sale you products. Glen argued with me about changing the filter until he saw my issue with the filter in my furnace and suddenly changed his tone. He also tried to sell me a humidifier but admitted he didn't have one in one of his homes. If it's a necessity then why doesn't he have one? His personal conversations about gun ownership and blaming Biden for illegal immigrants and telling me to purchase a gun were also offensive and not something I wanted from my HVAC person. Bottom line, for my $90 I needed a person who was respectful and provided excellent customer service. I did not get that with Comfort Zone so I can't recommend your services.