Hello @Bec1,
If the guest doesn't have government ID uploaded to Airbnb already, and if doing so would make you feel a bit more secure, then message the guest asking them to upload ID. If they object then I'd take that as a bad sign and not accept the booking.
Also message them and ask for some information like the purpose of their visit, are they on holidays or working etc.
I judge by the ease with which they respond and the tone of the response. For example, are they defensive, guarded and not helpful or do they come across as helpful and friendly.
If they seem defensive, giving very short "yes/no" answers then I'd decline the booking.
Be clear in your house rules as to what is allowed and what not. Longer term guests can sometimes get to feel like it's their house when it isn't.
Steve.