This is an interesting propostion. My mother in law is in her eighties and living with us. Because of her degenerative and painful back condition her doctor has put her on morphine (a "hard drug")to relieve the pain. I guess I can't tell the neighbors though right? Less all our property values decline should this get out right?.
Whatever, I grew up with people and got to know people. All kinds of people from different walks of life...still just people with this or that difference from me of some sort. That's life.
My recommendation is that you get out sometime to experience life without worrying so much about your stupid property value. IOW's, give life and the people around you a chance. Besides,chances are your property will be a heap of rumble a hundred years from now...so what?
Now if you and your neighbor have some sort of rock solid granite home that will last a thousand plus years, then I would still say you both (regardless of addictions if any) have the right to be secure and safe in your home and property in the here and now.
The difference here between you and I is that you don't believe people have a right to be secure and safe in their homes while I do. To go further, I believe folks have a right to smoke, drink, and do whatever drugs they want in the privacy of their homes.
Moreover, I believe folks who want to snoop under the neighbor's bed rationalizing their perversion that it is to "protect" their property "values," are a pathetic breed of miscreants not worthy of human status.