The typical scams are easier to catch and identify.
There are other schemes that can be more complex than the most common place money milking tactics used in the wider market. One thing to remember is that not every replacement or suggestion has a nefarious motive behind it. I’ll continue to emphasize the fact that most workers are honest and seek a good reputation. We should always keep an eye out for the common methods practiced by technicians who start sounding like a sales representative. But there’s a small group of expert con artists out there who put time into their craft. It’s been exposed that some car mechanics will intentionally sabotage something while underneath a car to get another sale. Some people have had their tail lights replaced then notice their blinkers don’t work. These crooks were only busted because they were filmed by hidden surveillance. If it happens in the auto repair industry, it certainly happens elsewhere. If a veteran HVAC expert starts talking in technical terms that a normal person would not be familiar with, he/she is most likely trying to make something more complex than it really is. His/her intention may be to intimidate you so you will be less willing to question the evaluation. If the HVAC tech says he/she wants to test some “new technology” on your forced heating system, be aware that he/she is doing so to tell you how inefficient or outdated your system is. This is usually followed up by a comparison of energy savings or environmental friendliness. One thing you could do is take pictures of the internal AC unit parts before the inspection. You can also do what customers have done in mechanic shops, install a hidden camera on your property.