I've got two teens DD 16 and DD 17.5. Both are pretty social and like having their (mixed) friendship group around.
My rule is that they all have to leave at 10.30pm if they come at night. Mostly, I encourage them to come in the afternoon, then go out. And not more than once every month/6 weeks. And sometimes I'm even there upstairs so I can call out issues.
Does that sound reasonable? We've just moved into a new rented house so I'm a bit jittery about it. I try to be really considerate but obviously they make noise.