That will be an important piece to this depending on how you plan to source your capital.

Providing relocation assistance to tenants, for example, if I want to sell the property or move back in - this can range from one month's rent to thousands of dollars (e.g tenant has a disability, minor children, elderly it will cost you more), depending on the city.

It's not what I would call a super rough, probably different street by street, and would most likely depend on the neighbors right around the property. 

Expect rates to be higher than "typical" financing programs - right now, I'd plan for at least 8%+ depending on the whole scenario. 

Still have to be careful though, with the block-by-block challenge, depending on the Class of Neighborhood.Also, be sure you understand the difference between the City of Detroit and the suburbs!

You get to take depreciation on an appreciating asset, you can even get tax credits for various projects and actions which depending the level your at equals a pay-day. 

If everything in the neighborhood is 90 DOM (market dependent)..

With investor's properties, depend on how risk averse they are, I fall under either just follow their criteria or maybe coach them my insight if I feel they are open to ideas.

All depends on what your goals are and what market fits your game-plan/criteria 

I only buy in vacation markets that depend on tourism to keep their area going.