To all those of you who are saying 'my house, my rules' - you need to be very careful about this..
As your children grow up, this is something that does have to be negotiated if you are to develop a good relationship with them. As a parent you have to recognise that you no longer control what your child is doing every second of the day.
Hopefully, by the time they reach 18 they will understand what is important to you as a parent. They will know that their room has to be kept tidy, they have to do their chores - or whatever you have instituted in your own families. But you do also have to cut them some slack as they make the transition from child to adult.
Your job as a parent is to help them become independent adults.
And this does mean that you have to let them take risks. It's unavoidable.
So put in place as many 'safety nets' as you can - e.g. making sure they text you, having a taxi account, staying over with friends - or whatever it might be.
I get really cross with my DS1 if he fails to live up to these things. But I would rather we had these battles than he was made to behave like a 12 year old.