Hey Shana - just wondering do you know if they own the house or rent?
I had this SAME problem and out of my experience I would not call the cops. That is what my neighbors did and since than their house was egged, toilet papered, Mail was stolen and than their car was broken into. It is not right what they did but really there was nothing the cops could do since there was no proof they did it.
What I did was call the landlord and told him anonymously of course and finally after enough calls and enough neighbors helping me do the same thing - the land lord kicked them out. AWHHH...freedom at last!
I hope you find some resolution because I do know what you are going through - except my neighbors were also dealing drugs
which made it even more annoying to me.
