Strongly suggest you make a police report at the nearest station, bring whatever notice / documentation / information you have re the incident at your home.

Even if this is genuine case, at least the police have a record of what is going on.

agree,
so the next time they come over can show them the report and their face(if you have cctv) that whatever his next actions will be follow up by police if he act out of the ordinary.

Scary, sometimes it's a trick just to get you to come out of the house.