Honestly, I don't think anyone can answer this, since it is so situation specific. But this is somewhat new to me, so any experience from others might be helpful.
DS is 16 and mostly hangs out with two other boys from school, long term friends. In recent years they've always went to each others houses for NYE, play computer games, hang out, etc.
This year they've all been invited to a house party, boy from the same school. I don't know the boy's parent(s), but know the house he lives in (large country house probably great for a party!) about 12 miles away.
Tomorrow I'm going to phone the parents, and confirm that he really has been invited, get times, more details, etc.
Any experiences of new year house parties with mid-teens?