Set a time limit on how long your adult childiren can live with you after college. And consider charging them room and board.
I would say 1 year seems like a reasonable amount of time for junior to get on his feet, find a job, save up some money and find a place to live.
But don't go supporting them financially after they have moved out too, they need to learn to make it on their own and live within their means.
And no I'm not talking about emergency situations that come up. I'm talking about the kid who shops all the time and eats out, and then can't pay their rent.
We don't have this problem, with 12 kids still at home, the older kids can't wait to get out of this zoo.