i've had similar experiences in the bay area with in-your-face unsavory stuff happening right out in the open. the climate is mild and the rents are sky high, so the sleazeballs are right under your nose instead of behind closed doors. either you pitch in and get your neighborhood so fired up that it organizes to deny the difficult people their habitats, or you just accept the fact that there's a travelling party which has identified your personal turf as the weakest link.