That is TERRIBLE D: I can't even imagine being mean to my mother on purpose. I think kaliope is right though, people don't often understand how nice they have it until it's taken away. Especially with kids who think they can take and take and take, sometimes it is best to give them the bare minimums. Especially if they're getting that ridiculously rowdy.

Give them a phone with only restricted options of calling home or emergency numbers. Block the internet from them unless they need it for school and then have the parental controls on verrrrry tightly. Use a lock to stop kids from finding and plugging the tv and games back it (Lock the hole in one of the plug's metal prongs). Do things by the reward system. If they behave they can make a request on what they would like for dinner. If they don't, give them brusselsprouts and meatloaf while the parents go for a nice dinner out. Replace their entire wardrobe with old handmedowns or if you want, have fun with it and only give them animal printed everything. Remember to lock your door though because revenge can be rough.

Best of luck!