This is petty and childish, so please move on if petty things irritate you. However, if you don't want to engage in a sonic arms race, which may or may not work

This is petty and childish, so please move on if petty things irritate you. However, if you don't want to engage in a sonic arms race, which may or may not work, I have a suggestion. I had a similar problem with downstairs neighbors some years ago. My city does not have a noise ordinance, as crazy as that sounds, so calling the police wasn't going to work. I gave these dudes three strikes, being as polite as possible, because I really believe that neighbors should get along. Also, I used to be just like them. Having good relationships with your neighbors is very important. Anyway, I had access to both my and their air conditioning units in the attic above my apartment. I bought some of that stinky fart liquid on Amazon for a few bucks, and just continually put drops into their duct. I would crawl up into the attic once every couple of days and hook them up. The smell was atrocious, and inevitably I would hear the windows and sliding door open and raucous complaining after administering the juice. I did that for about two months, towards the end of their stay. Also, I bought a can of paint, opened it and took it downstairs at 4am one Tuesday morning, and kicked it over on their front stairs area, near where they stored their own cans of green paint. I also got a hold of a bunch of beer bottles and cans from their patio area (I guess they were planning to recycle them or something), and put a ton of the cans just on the other side of their back porch fence, where they couldn't see the cans on the ground, but the property manager could. Finally, I made sure "the main guy"'s car wouldn't start so that he wasn't able to make it to work. Tailpipe blockage will prevent a car from starting. That was the final straw. They were out shortly afterwards. If you go the guerrilla route, you've got to be as quiet as a mouse. If you complain loudly to the neighbor and also to the property manager, they will know exactly what's going on. Be creative! But don't hurt anyone.