By home alone, I mean with no other adults there.

This has been a dilemma for me because I've heard many stories of thieves going around to see if any homes in the area are empty, and we don't keep cars parked in our driveway so if I don't answer the door it does seem like our home is empty. But every time I answer the door it's someone claiming to be doing work nearby or some other slightly scam-ish story.