Sid Kirchheimer has some valuable columns at AATP on scams, recently door-to-door sales scams.
One such scam involves home security systems, as he explains on July 7, 2016 here. He has a more recent column on p. 16 of the September (Vol. 57 #7) printed membership newsletter (not online yet), “Who’s that knocking” where he talks about a lot of other door-to-door scams.
On my “IT Job Market” blog, Aug. 15, 2016, I questioned whether door-to-door selling should even be a legitimate business practice today, given the practical home invasion risk. But then, how do a lot of people even make a living if too many of the “haves” are hunkered down, with no one watching their backs. In past generations, door-to-door was a legitimate occupation. Maybe no more.
In fact, a pest control contractor told me that “no trespassing” signs only attract (or perhaps anger) the more aggressive D2D sales people. This presents, as they say in “The King and I”, a puzzlement.