The technician did a very good job overall but there were a few things that could be improved:
1. At no time when the appointment was first made and when the technician arrived was there an explanation that an A/C system assessment would be done in connection with the air duct cleaning. I did not ask for one when I scheduled the appointment. Although a few minor problems were discovered during the assessment to my surprise the cost ballooned from $450 to over $900. Sorry but on a fixed income (retired) that is a LOT of money.
2. Again, I have no problem with having required maintenance performed. I just wish I was notified ahead of time. With the cost of the work "doubling" it just left me with a bad taste in my mouth. It seems almost like a "bait and switch" tactic, which certainly is not acceptable.
3. I only agreed to the "sanitizing" of the A/C unit due to severe allergies I have been suffering from.

I think the bottom line is the need for thorough communication. When the appointment is first made the rep needs to explain to the customer that an A/C system check is part of the service call.
Other than that, the technician seemed very knowledgeable and worked very diligently while he was here.