You'll want to think through marketing, screening, leasing, payments, maintenance, and a whole lot more.

She already knows anyone staying for more than 1 consecutive week, or 14 days in a calendar year, would need to fill out an application, pass the screening process, and be added to the lease.

Look at Ivy Flats.

  $100 cash flow per door is another one of those rules of thumb that can help you screen properties, but doesn't necessarily guarantee a good deal. 

I'm currently in the process of getting my Hamtramck duplex house hack up and running, I'm currently in the tenant screening phase.

After those potential tenants passed my Pre-screen*.

Here is a screen grab from my analysis spreadsheet.

He is kind of a fast talker and kept jumping around.Is it as simple as its a flat 40% at the end?

@Jeremiah Vancans You will be able to find better cashflow in the D-C class neighborhood if you dont mind the drive and headache of dealing with tenants (proper screening can mitigate alot of risk on tenants). 

Scroll to the bottom of the screen.