@A-t0
1) yes we do, in Croatia it is mandatory and we register our guests to the police using the online form.
During the check in my guests have to show me their photo ID (passport or ID) and I have to write down following info: Name and surname, is it passport or ID card, document number, nationality, country and date of birth, country and town of residency and is it male or female.
On the top of this form, it is written my VAT number, my name and surname, Address of my ABB unit,
On the bottom of this form I write how many keys I gave to my guest and the person who booked has to sign it.
If there are more people in the group then sometimes I just take a photo of their ID-s to speed up the process.
It has to be disclosed in your listing that your guests will have to show you their photo ID
2) to avoid sex-guests the best would be to decline guests from your city.
Put in your house rules that visitors and unregistered guests are forbidden.
You can install a security camera in front of your entrance but it has to be disclosed in your listing as well.
Give your number to a good neighbor and tell him to call you if he notices something weird is going on.
For the beginning don't use instant booking but vet your guests up front, ask them what is the purpose of their trip etc.... and trust your gut.
Check in your guests in person.
Good luck 🙂