That sounds terrible and I can imagine how it is for you as I’ve had a similar problem. I assume he’s an owner which makes things a bit more difficult, though you don’t say he owns. If he’s a tenant, I’d be pulling out all stops to find the property owner and deal with it that way, via the owner.
Tenant or owner, I doubt you’ll have much luck with any Strata Manager or Strata Committee on this one. They just won’t want to be involved and what could they do anyway? Nothing.
The police? In my experience, even if the police know him, know about him and have incident reports and court cases with him coming out of their ears… they’ll do SFA.
The best advice I can give you is, since you’re tenants, move as soon as you can. I know, you probably like it where you are and are used to it. But do some research first and then get out while the going’s good. And keep your wits about you until then. Get a little CCTV WyzeCam 2 online, just in case. They are so cheap and absolutely fantastic. I have two, inside looking out which is legal. Can you set one up looking out, yourself?
Our nasty guy moved away two years ago but still comes back and sprays paint on our car and stuff, every now and again, believe it or nuts.