What's the harm really?

I had some of my buddies go to rehab and such for substance.

make it a part of your business policy so you can be consistent and not accused of unfair housing practices. it can be unpleasant with an unresponsive or difficult tenant but if the tenant is damaging your property or not abiding by the terms of the lease, ultimately they are harming you. 

I do not know the legality behind not being able to change locks if the property has not been occupied, but do not see the harm in trying to secure your property in the meantime.  

Yes, as usually happens, laws designed to "protect" people (eg discrimination) end up indirectly harming those they meant to protect. 

After all the sole focus is collect your rent so who cares if this does actually exist and could do harm both mentality and physically. 

They are have a wealth of issues (untreated mental illness/substance abuse etc) that would need to be addressed before suitable housing could be found.

Pithy [ pith-ee ] SEE MORE SYNONYMS FOR pithy ON THESAURUS.COM adjective: brief, forceful, and meaningful in expression; full of vigor, substance, or meaning; terse; forcible: a pithy observation."

I don't want to make this a political post by calling out specific policies or political actions that have been harmful to economic expansion in the area.3) I agree with the infrastructure issue in the area.

We don’t know any PMCs to recommend in the area mentioned, but since selecting the wrong PMC is usually more harmful than selecting a bad tenant, you might want to read our series about “How to Screen a PMC Better than a Tenant”:https://www.biggerpockets.com/member-blogs/3094/91877-how-to-screen-a-pmc-better-than-a-tenant-part-1-services-and-processesWe recommend you get management contracts from several PMCs and compare the services they cover and, more importantly, what they each DO NOT cover.