You may could give them a license to use the land, provide a temporary or revocable easement or otherwise permit the use in some way.

The $56-a-unit process requires landlords to be up-to-date on their property taxes and for the properties to be free of any safety or building-code violations.Since landlords are not legally permitted to collect rent from tenants of a home with an inactive license, the system is designed to serve as a check on property owners, forcing them to address safety violations and pay their taxes.But Philadelphia’s Department of Licenses and Inspections lacks the resources to hunt down property owners who flout those rules, said Karen Guss, a spokesperson for the agency.

I think he calls it "pre-development" & goes over subdividing, entitlements, permits, etc.  

NYC DOB considers a shelter a 'community facility with sleeping quarters' and may require a special permit for this use.Thanks Abel, You provided me with the right search terms to dig deeper. 

Another consideration is the permitting process and local zoning quirks, which can slow you down or force design changes mid-stream.

The job starts when paperwork begins , ordering materials obtaining permits , lining up subs etc .

From simple rules like permits to outright bans so that is a huge risk IMHO.

Our local towns and rental assistance programs really appreciate those that try to work with their tenants which has helped me several times through easier permitting processes.

If your leasing application process is thorough and well thought out, and if your lease agreement has been well drafted by your local attorney and if it includes clauses that permit you/your property manager enough latitude to maneuver and anticipate undesirable tenant behaviors, both actions and inactions, and you have operational processes which align with enforcement of your lease, then you've done all you can do to reduce this inherent risk of an undesirable tenant.  

Does that mean I'm all set and can break it up in to separate units, or do I need to get a permit or rezone or other things?