My DS was an intolerable little git from about 14 until about 15 and a half. By the time he got to 16 he had come out the other side.
We had arguments about it all initially, and we had a few months when house was just full of negative energy, but then I thought "bugger this, it's far too stressful" and I stopped arguing about it.
But what I said was "OK, you think you are not a child, so I won't treat you like one".
I didn't include him in the evening meal planning if I didn't hear from him and I made it very clear that mum's cafe closed at 6.00 p.m so if he wasn't back for dinner, I wasn't doing anything later.
Laundry - you are not a child, sort it yourself.
College work not done? Oh dear, you are not a child, deal with it.
More money on your card? Explain why you think that's appropriate.
If you want nice things to happen, behave nicely and appropriately. Treat me like shit and you can whistle for the crisps you like, or the squash you like, or the Greggs I often pick you up on my way back home from work. Bye Bye nice things.
Etc, etc.
Honestly, initially he liked the fact I had backed off, but after a week or so it wore thin and his attitude did change and he became a bit easier to deal with.
It's a hard phase. But look after yourself first and foremost.