[Freak_NL]

Stop looking for a technological solution to a people problem; move.

There is nothing you can personally do to make them stop legally, and anything you do illegally comes with a risk to your personal safety. So if the police won't uphold the law for these guys, your best bet is to simply get out. Improve the quality of your life by living somewhere else.

Other option: just wait it out and see if the problem doesn't go away on its own. This may fail though.

[FernandoMax]

Great technique to push people for selling houses, so accepting down price deals. So maffia can buy the properties for the cheap and then do whatever to make a profit.

Step two: Repeat at next neighbourhood.

Solution: Noise isolation windows and walls. Costly, but it works. Isolate from the outside world, including installing an AC machine.

[the_italian_job]

Sadly moving is not an option at the moment.

Probably, as someone else suggested, the only option is to invest in audio insulation and a good AC.

[Freak_NL]

Proper sound insulation is expensive though. If moving is not an option because of financing, you might want to save money to be able to move eventually rather than spend it on a property that's making you miserable.

[bradenb]

This is the right solution. It really sucks, but feels like it's out of OP's hands. It's not worth the risk to personal safety.