The reason I mentioned/asked if it was council or Social housing was that you stand more chance of the landlord taking action rather than if the property was owned by the occupants.
Obviously it also makes one wonder why the police already have CCTV installed in the street, where I live was to keep a eye on all the drug dealing that was going on.
If there is anything you can pass on that might be of any use to the police then I would suggest you make a appointment to go and see your local police neighbourhood crime prevention officer, if you are fearful of your well-being with attending a police station in case you are seen then they can and will make arrangements to see people away from either the station or your own property, at places such as a hotel etc or even just a pub away from your area.
But unfortunately it may have been quite so far today, but with hind-sight (10 years of it) these problems do not just fade away into the distance without some form of intervention. If the parents are threatened with eviction then they may just make their son stop.
