Thanks for the input, everyone.
Al, I think your advice is right on. Evidence is that the current owner is not a hands-on owner and has trained the tenants that they can get away with quite a bit. I suspect (hope?) that that's the biggest issue with the place.
I'm very ready to make my presence seen and felt on property if I buy it, and to let it be known that there's a new sheriff in town who's not going to put up with the stuff the old owner put up with. Joel, I'm willing to put in the time and have my feet on the ground onsite to protect an investment.
I guess my key question is, if I do put in the time, and make changes, such as evicting nonpaying tenants, deadbeats, and troublemakers; and let it be known that I will provide a clean, safe place to live in exchange for tenants who keep the property in good condition and pay rent on time; and if I'm regularly seen onsite and spend time talking to tenants and letting them know that they'll be treated fairly as long as they hold up their end of the deal; and if I am consistent about enforcing those policies... is that going to be sufficient to turn an inner city underperforming apartment into a profitable investment?
I'm willing to put up with 3-4 months of pain (vacancies, vandalism, evictions, etc.) as everyone learns that the new landlord means business. My concerns is whether or not the pain is likely to persist after the message gets out there.
(I do like the links to the block party and neighborhood watch ideas. Thank you!)