Yeah, people love going for the soft targets or attacking someone that's visible and easy to blame. For some reason, it seems that being deemed a "low-life" absolves that person of the responsibility for their actions and people criticise the reasonable person as it feels safer. After all, if you criticise the low-life then they might start a vendetta.
I don't have any expertise, but I would probably guess that you should quietly encourage disgruntled neighbours to call the police. If a police report were issued, even if it didn't recommend further action but simply a complaint, then that can give you leverage and you're covering your bases if the tenants kick up a stink and take you to the tribunal.
As a renter myself, I absolutely loathe noisy neighbours. It disturbs the peace and tranquility of my refuge, my cave, my territory. So I can understand the neighbours attitudes. You could see this as an opportunity. Go and have a cup of tea with some of the neighbours and have a chat (if you're so inclined). Apologise on behalf of your tenant and accept responsibility and go overboard with the self-criticism.
It's not because you are actually responsible, but it quickly turns righteously indignant people into allies. They'll place the blame on the tenant to keep the harmony and good feeling of the situation and then you'll have a chance to create a second, informal property manager.
You might try saying: "You know what, I sincerely apologise for the disturbance, I hired a property manager (if this is true) and they chose the tenant, and as such, the buck stops with me and I take total responsibility for this injustice (perhaps not fair, but it's the classy thing to do). I understand that you have a right to enjoy your home in peace and that you're a busy person who needs to know they won't be disturbed at home (make them feel important). I'm going to do my best to make it up to you and I was even hoping you might have some advice for me."
Then listen, hang on their every word and keep making them feel important. At the moment they feel their ego has been hurt and that no one is recognising how important they are. Bring them in and they'll repay you by doing everything they can to help. An irony of human interactions is that the more you help someone, the more indebted you feel to them! Messed up, isn't it, but true nonetheless.
Then you give them your number and tell them to let you know whenever there's any issue they're having witht the tenant. Give them your landlord's number and tell them that if they can't get hold of you they can call the landlord. And suddenly, you have another person on your side, and they'll win the others over too. You're the good guy and they'll go out of their way to make sure that your tenants are well behaved. If they're trashing your place, they'll let you know. If they've got lots of extra people staying over, they'll let you know.
Give someone what they want and you'll get everything you want from them. But it's important that you're sincere and that you lead with the giving hand. Failure to do so will create the opposite of what you desire, it'll create contempt and disgust.
It should go without saying that you are equally as savvy in your treatment of your tenants.
That's my 2 cents, but you may want the opinions of someone with some direct experience in these matters.
