Here was an in-person attempt on me a few years ago:
It was a weekday afternoon, I was out doing some trimming on a front yard oak tree. A guy came by slowly in a pickup, and stopped on the street. He came over to talk to me with a stack of papers in his hand. He gave one to me. Black and white copy, hand written. It had his name, phone number (with an area code of a city at least 3 hours away). Said he was a degreed Arborist, degree from UT (Austin). He told me he was in town visiting his mom for a couple weeks, said she lived on the north side of town. I asked him whereabouts, and he gave me the street and where it (the street) was. I knew of it well. Said after he was "home" for a while, his mom got on his nerves and he needed some time out, so he was doing some tree trimming work here and there. He said he could do whatever I needed done, would only be $100. I told him thanks, but I do my own work. I think he rapidly assessed by my comments, knowledge, and equipment, that I knew what I was doing and he wasn't going to get any $ from me. But he wanted to leave the sheet with me in case any neighbors needed someone.
When I was done working, I set it down in the house, a few days later I threw it out.
Skip forward at least a year... read an article about a con man scamming people in my town and surrounding area. The same guy! I remembered his name! Scammed a guy out of something like $1,800 for tree trimming that little work was actually done. He convinced the homeowner that what the homeowner wanted done would cost much more, or else he couldn't finish, needed the $$. He got the money, never did the rest.
It was in court, article said that he had been in state prison for the same kind of fraud, was released not long before he stopped by my house. The trial result was to send him back for another stint of free room and board.
He was a good talker, but he was too good. He jumped on everything I said or asked with an immediate answer, even when it was wrong! I can imagine, though, that if he found someone who wasn't comfortable doing the work themselves, and didn't know much about it, that they might be taken in by his friendliness... evidently!