Over the years I've had a few different tradesmen do work for me. I've had a plumber (he installed a combi and nine radiators), I've had an electrician and he checked my wiring and did some working making safe the dodgy DIY that previous occupants had done, I've had a roofer fix bits of my roof, and I've had a plasterer plaster most of my house.
I treat them how I expect to be treated. I asked for a quote, agreed a price and a work schedule, and then let them get on with it. When the job was finished, I paid them.
I didn't say, "No, I don't like electric drills; you'll have to use a hand drill", or, "I don't like that modern plaster, it's cheating, I want the horse hair and cow poo plaster you mix in an old bathtub", I just trusted them to get on with the job and do it the best way they see fit.
I don't let my customers dictate to me my working practises; I'm self-employed and they are not my employers. I'm polite, and on the rare occasion it's been brought up, I let them know that I do the job the best way I see fit.
It's best to get rid of people who mess you about sooner, rather than later. Bad customers are easily replaced.