Hi Keita
So glad you got your hackles up! I notified Airbnb of my suspicious inquiry, and they in turn assigned a "security" person to my case. He gave me a few tips which I'll pass on to you:
1. You should not give the street address out to anyone at the initial inquiry. Airbnb has the street address and keeps it private until someone has a confirmed booking. They cannot get either your last name, or address unless they book.
2. You do not need to photograph everything in your house. You choose what you want shown, and that's what's posted. You do not need to send additional photos to anyone.
3. Most importantly - the best way to handle an inquiry which seems inappropriate is to basically refer to Airbnb's policy. In other words, what I said to my suspicious guest was "I'm not going to share the street address with you unless you book, per Airbnb's policy. I'm sure you understand as it's a safety issue."
I happened to follow up after this exchange with a notification that I am a member of a neighborhood watch team, and that I have a property manager located within a few blocks of the residence. This gave me peace of mind, so that if it is some kind of "gang of thieves" looking to root out unoccupied homes filled with sound equipment, televisions and game consoles - they ought to look elsewhere!
4. Last tip is to go through the verification process. Apparently, if you verify yourself as a host via Airbnb, then you can require that your inquiring guests be verified as well. You should contact Airbnb directly for more information on how to do this.
Good luck Keita! I still don't know the outcome of my suspicious inquiry, but he disappeared after I told him I wasn't going to share the address. I've emailed him twice since then to check in (giving credence in case it was a real inquiry!) and he never wrote back. I think that proves that it was some sort of fake inquiry looking for more info.
Best
Liz