If you give up today, you are guaranteed to never find a good deal.

I guarantee the fire marshal would back you up.You could be nice and offer to install a $200 bike rack outside the building, but I would not compromise on storing personal items in common space. 

While the rent is guaranteed, I learned that the maintenance issues far outweighed any rent guarantees.Section 8 conducts yearly inspections which is great. 

But, could I minimize risk of renter defaulting on payments for the 2nd property by turning this property into a section 8 housing unit with guaranteed income from the gov't?

While screening tenants properly is not a guarantee to avoid this, it certainly is the best way to do it.

But, could I minimize risk of renter defaulting on payments for the 2nd property by turning this property into a section 8 housing unit with guaranteed income from the gov't?

While you can’t guarantee this often you will get a gut feeling.

The only quick number there might be is doubling the cost of materials to add in labor, but that's not guaranteed - some jobs have few materials and a lot of labor and others are opposite. 

DSCR is about a non-recourse loan (secured by the property and the property performance, not by the personal guarantee).

It's all money back guarantee, blah, blah, blah.