@David-and-Annie0 Yes, the lock-box question is cause for suspicion. Perhaps dialogue further with this guest to get a better sense of his intentions, what kind of group this is (family, friends, work colleagues), whetever you can think of to ellicit some further information and get a sense of this person. Make it clear that no unregistered guests will be allowed on the property. Since it's two months in the future, you don't have the pressure to decide to cancel it under the "I'm uncomfortable" like you would if it was for a few days away, so you can give yourself a day or two to decide.
I have a few comments on ways you might tweak your listing info- the place, by the way, is gorgeous. You make it clear that it's geared to families, with things provided for the kids to do. Yet many things in your photos are not that in line with having a bunch of kids running around- breakable little vase on the doorside table, wine bottle holder at kid-level, white carpeting throughout. You can ask guests to remove their shoes, but do you really think they all will? Maybe take some photos with kids' books and toys around, to convey the family nature of the place. Aside from the obviously kid-themed bedroom, and the little table with kids' dish setting, most of your photos send an "adults" message.
I don't think it's wise to reiterate under "Entire House" that they'll have the place to themselves. That's already what Entire House means, no need to reinforce that idea in guests' minds, as it's what the party crowd looks for.
Under "Interaction with hosts", your wording is unclear- you say you're there, but what does that mean? Do you live on the property in another dwelling? Close by? If you are close, make that clear- it can help ward off the party crowd. Also you haven't stated anywhere (unless I missed it) whether there is self-check-in or you will be there to meet and greet and give an orientation. So in a way, the guest's question was valid, as you don't state check-in procedure. If it's at all possible, I'd meet the guests on arrival, at least until you get more experienced, as your place definitely looks like the perfect party house.
Also, you mention a bunch of fines for not respecting various house rules. You can't charge fines for breaking house rules on Airbnb- all you can charge for are actual damages. It's up to hosts to enforce house rules and if a guest violates them, you can call Airbnb to explain the situation, and ask that the reservation be cancelled with no penalties to you, but it will actually be up to you to make sure the guests leave in that situation. And they'll be refunded any unused nights.
And I really hope you have private insurance that would cover you in case of damages- you can't rely on Airbnb in the least to do that.
