My old man is the one to answer the door, and the conversation went something like this:
Scammer: Hi, I'm going around the neighborhood offering a free home security system, and all you have to do is put a sign of our company in your front yard.
Old Man: I really don't like to advertise my security system in the front yard.
Scammer: Well, the sign won't affect the security of your home.
Old Man: I really don't like to talk about security systems with complete strangers. Bye.