All you can do is find a new place to live.
You have a choice of making his life miserable by posting negative reviews on all the online reviews sites (google, yelp, etc.) Setup a facebook page denouncing him. Heck, picket his properties, or even his personal residence from the sidewalk in front of his home if that gives satisfaction.
Or, you could decide that you are not willing to let this jackwagon have rent-free space in your brain, put it behind you, and move on (literally).
Let's at least hope that his new tenants turn out to be deadbeat thugs that destroy the place, cook meth in there, and skip without paying the rent.
