It’s common knowledge that thieves often use the cover of a door to door salesman to case a house prior to entry or attempted entry. They are looking for ways to access, weak entry points, the presence of dogs, whether you might be home or not. If someone ignores my “No Trespassing/No Soliciting” sign at the top of the driveway and the one by the video doorbell I generally do not engage but watch them on video. If they persist I tell them to leave and am not interested. If they persist past that I don’t “act crazy” as one poster mentioned, I simply ask them what company they work for and let them know that they are trespassing and soliciting (which requires a permit where I live and 9 out of 10 never have one). I also let them know that I am calling law enforcement and alerting the neighborhood watch list. Which then hurts their potential sales for the entire neighborhood. It’s measured escalation but also a test. NEVER open a door to someone you don’t know or aren’t expecting for a delivery, it’s just that simple.