everyone has their own style of doing business and I say "let the market dictate" if his properties are that bad, eventually even the druggies wont want to pay him to live there.
Also, leases have various clauses so perhaps his properties start on in working, liveable condition but the leases stipulate that all repairs to be made by tenant. My leases state that items costing under a certain dollar amount are to be fixed by the tenant. This keeps me from getting calls to change lightbulbs, and toilet flappers.
here in tampa we have a huge drug problem with street prostitution and shady motels and hotels. A friend that is a cop in the area was telling me all about it one day. The sketchy motels rent ROOMS, not apartments but ROOMS for $30 a day and the vast majority of these rooms are utterly disgusting, dirty and gross but these addicts keep on hustling and prostituting themselves for that $30 a day or else they are on the street. it's Florida, it's 90 degrees + for 8 months a year. IF all those motels suddenly shut down, where on earth would all of those people go?
There is no easy answer to these problems.
I own one house in "the hood" i scored it for 25k and decided to put 35k into it to make it a beautiful brand new house. it's got granite, stainless appliances, real wood cabinetry and nicely designed bathrooms and tile flooring throughout. part of that was to make it more durable as a rental but the other part was me believing that if you give someone something nice to begin with, they are more inclined to keep it that way. As a result, i have been getting much higher rents than others in the neighborhood. I do get some prospective tenants that are priced out or shocked when they hear the asking price but then when they see the place they almost always say, "damn, it's worth what your asking, I just can't afford it" I took a big risk in the ghetto on being able to find one person willing to live in the neighborhood and willing to pay the asking price and so far, it has been paying off big time for me. I dont have to rent the house to everyone, I only have to rent it to one family.