Animal House?

Don't know if it is a generational thing or a lack of security in my apartment house but over a period of time it seems more like party central than an apartment house and now the moving party has moved to the unit next door to me.  Unlike people in my generation who would visit friends around 8 PM for a few hours, these kids do not even get started until about 10:30 PM.  Then last night, as in some other nights, people were coming and going at all hours.  I was still awake at 3 AM today due to all the activity just outside my door.  In my day, people respected their neighbors and did not talk so loudly.  Then too, this building has paper thin walls, not the good old lathe and plaster of my father's house.  Then there is the matter of who exactly rents the apartment next door.  I think it is a slightly older woman but the people coming and going late at night, from what I can see, are all or mostly in their twenties.  Looks like frat house during spring break at times.

I am most concerned, and this may be my paranoia showing here, that the occupant of that apartment doesn't even know who is coming and going, that she might have loaned her key to someone one day and that person made copies for all of their friends.   Or maybe it was stolen.  So, in effect, the door is always open.

So I am wondering how I should handle this?  There has been no resident manager since Don passed away and the property management company is in San Mateo, not San Francisco.  Oh what to do, what to do, wtd, wtd?