Have you told the cops about the harassment? Cops take that seriously nowadays.
I had some hostile tenant applicants and an ex-tenant who wanted to move back into the building, and I said no. Both harassed me in different ways. One would bang on the door and yell at me, the other was calling and threatening to come lurk around the property until he could find the owner to talk to (convinced the owner would let him move back in LOL!).
Anyway, in both instances I called the office desk line at the police dept to talk to someone about what was happening. They sent an officer to my apt (resident manager). Both times, the policeman telephoned the "offender" with their cell phone in front of me. They explained to the person that they could be arrested for harassment if they didn't knock it off. The cops were very polite, listened to the person going on about how they were being treated unfairly, blah blah, but then the cops said, well, that may be so, but you will get arrested if you keep doing this.
Both times they both stopped bothering me immediately.
This is a different issue than calling cops for a noise complaint. So, if you haven't called them on the harassing and the following you and blocking your car, banging on your door (which I think is worse than banging on the walls), I think you should. They may nip this in the bud pronto.
Sorry for the hassles. Glad you're moving.