My 18 year old son has just come home from Southern California after trying to move out on his own, and not being able to find a job. He had a little money left him by a grandparent, and he blew it all, then couldn't find a job. He enrolled in junior college, and then dropped out after a few weeks. He has been staying out late, partying, and sleeping all day, and trying to support himself by doing tattoos.
I haven't said a word, because I already made clear to him that if he wants the privileges of an adult, then he has to take on some of the responsibilities, too. I already told him that tattooing is not a job that is going to support him, particularly since he doesn't have a license or a studio. And I told him that starting next month, he will have to pay me room and board every month, and unless and until he is enrolled in school full time, he will have to pay me room and board, or he will have to move out.
I haven't put any curfew on him, or tried to get him to spend time with me, but this is not a hotel---as long as he's in my house, he has to do his share of the chores, and he has to pick up after himself, and he has to mind my house rules--- basically, his friends are always welcome, but no alcohol or weed on the premises, and no tattooing of people under 18 in my house.
He already knows that I don't like him drinking and getting high, and he knows why, so lecturing him about it would just be counterproductive. Sooner or later, he will figure out that all this partying and carrying on gets in the way of real life. I figured it out, thirty years ago, and so will he.
I think this is only fair, because I have always told him that when he's 18, I won't be telling him what to do anymore, and I'm not telling him what to do. I'm just letting him know that if he wants to party all night and lay around all day, he can't do it for free in my house.