I don't have a doorbell or dog. Occasionally someone will knock on my door, whether it's a neighbor needing a hand with something, UPS needing a signature, etc...I can peek through a different window and see who's there. If I don't know them and they knock a 2nd time, I will ask "who are you and how can I help you?" while standing about 10 feet away. I won't pretend I'm not home in case they are contemplating a burglary, but I'm not opening the door unless they give me really good reason. I live in a semi-rural area. A few years ago, someone knocked on my door at about midnight. Looked out the window and it was a young guy, early 20's. I asked what he was doing and he claimed a couple guys chased him and tried to run him off the road, so he pulled in the first driveway that had an outside light. At about the time he was asking/begging me to call the Sheriff, another truck pulled up in front of my house and 3 guys jumped out and headed toward my porch. The kid at the door hopped the porch railing and took off for the field across the road. I call the Sheriff's Dept and while I'm on the phone with them, the 3 other guys start vandalizing the kid's truck...in my driveway. Dispatcher asks if I have a gun. Of course I do. "If you want to, go out there and order them off your property. Tell them we're on our way" I replied that I for sure don't wanna be in my yard with a gun when the deputies show up. "Oh, it's gonna be at least 45 minutes before we get anyone out there. You can run them off or you can go back to bed and we'll call when we get close. Up to you"