Yes, that! Of all the pieces of this advice that bug me, the idea of not warning the elderly neighbors that the person they are letting into the house has a documented history of theft bugs me most. Partly because I could just see too many relatives in that situation, and partly because I've been the person robbed by someone I hired to do work, while being about 80% sure the neighbors watched it happen and did nothing (it was lawnmowers and lawn care, thankfully, but it still killed one more piece of my sense of safety, not to mention the ten-small fanperson's idealism - she had made the thief a peanut butter sandwich).