Mark is very professional and tells me truthfully what needs to be done to our A/C and heater units. I never think or second guess him because I know he is honest and not trying to sell us something we do not need. We have been a long time, loyal customer of Airmax and Mark is one of the main reasons. We have recommended Airmax to a lot of our neighbors and now they are forever customers. Scheduling and follow up is also top notch.... enjoy the whole experience with Airmax.