Another expense you will need to account for IF you buy a small multifamily is that the owner is resonsible for cutting the grass.

Does he have any skin in it, meaning he has any out of pocket expenses, or are they all on you?

Were the tenants not profitable due to continual expenses in repairs and inconsistent vacacy rates?

What are your expenses?

The lender will ask for some basic information, such as your income and expenses and they'll run a credit check.

Being in Brooklyn and the expensive market here, I am looking in Union City/ West New York area.

I am pulling the trigger on a much larger complex, though, and the depreciation expense is substantial.

Set aside for Cap Ex expenses and a reserve to support rental loss. 

Without getting into all of the details, it's an expensive proposition for a small duplex.Although seemingly better suited for large properties, I looked into a submetering system as an alternative.  

I did not have Flood Insurance, foolishly thinking my hurricane policy would cover this type of hurricane related damage (learned my lesson) I'm looking at expensive repairs and possibly a home that my tenant can no longer stay in (they evacuated for the storm as did I) which would be a loss of rental income for the foreseeable future, on top of uninsured repairs.