I understand that there are qualified techs, but I also know that the ones that originally installed my equipment did not ground it, did a sloppy job of running the cable, & when inside leaned their dirty sweaty arms all over the freshly painted walls. When I had them come back to ground, they ran a loose wire to the water faucet. I said that won't cut it & they said that is all they were going to do. When I pay for something, I expect it to be right.
unfortunately there are bad apples in every service business. So you are correct to be concerned.
Sweaty? That's why I bring a towel into the home with me when it's hot outside.. nothing bothers me more than getting my sweaty self all over the customer's house..
Now.....I believe it is the customer's and tech's responsibility to establish a repore prior to any work being done. Yes that takes more time but who cares. Making the customer feel comfortable with my presence in their home is key to a complaint free job.
There are far too many techs who are in this just for the money. They are always in a big hurry. Part of that rests on the shoulders of half assed fly by night contractors who load their people up with two days worht of work for a 12 hour day.
But as far as i am concerened there is NO EXCUSE for shoddy work, poor customer service and not doing the job correctly the first time. If it were up to me, poor customer service and bad workmanship would be grounds for immediate dismissal and blacklisting from the industry. These crappy techs and contractors who employ them have to be run out of the business. Until that happens, complaints such as yours and worse will continue.