I'm glad you do have that dead bolt on the door. Like Christina, I say it's not about gender. It's about all kinds of safety and privacy concerns. I've lived in rooming houses where I've shared an apartment with several strangers. We each kept our rooms locked, and I think that eliminated a lot of problems. No one took it as an insult.

That sounds reasonable about the new job giving you some sense that the guy probably has a pretty clean background.