I’d say you did the right thing by being suspicious. I had a guy come to my door two summers ago and wanted to clean my living room carpet for free. I asked, FREE? He said yep, and when he does such a good job, people ask him to continue with other rooms, then he gets paid. I looked out into my driveway and saw an old rusty cargo van with two other guys sitting in it. Shady looking, all three of them. I said no thanks I have my own carpet cleaner (which I do). Before he got back to his van I was on the phone with the police. Mine was the third call that day about the same crew. A few minutes later a squad car drove slowly by my home, but the carpet cleaners were gone. I have no idea if they ever caught up to them.