It's been at least twenty years, but I've seen the "van scam" a couple times. First time was at a construction site; I got suspicious when the guy kept changing his story about exactly what kind of speakers he had (he said they were home speakers; I wasn't interested in home speakers but could use some car speakers instead and lo and behold he said he had some of those too!). Second time was when I was in traffic and stopped at a red light and the guy pulled up next to me and motioned for me to roll down my window, By that time though there had apparently been a rash of these people around the area and it had even been on the news so I had been forewarned. This was all in the Chicago suburbs, 1990s era.