Usually it's some sort of flim-flam on construction or driveway repair. Last one was a scam on meat - "Hey, my refrigerator truck is broken down, can you help out, want to buy some, etc etc"
Had the meat scammer at my front door last weekend.
I once met one in a medium security prison. About 35 years old - did not know for sure. Born in America. Never went to school and could not sign his name. Claimed that he never had a Soc Sec number.
He said that his favorite scam was putting used motor oil on blacktop driveways. He said that he recognized fellow travelers by the particular type of truck that they drove.
I do not remember what his criminal charge was.