As you mentioned, that expense range is not super helpful. 

Somewhere in the middle is likely your best bet for a 20 year timeline.I have almost 50 units here myself and that's about what my portfolio is cash flowing at this point combined LTV is around 65% as loans have gotten paid down and values have went up.

You'll get to write off any home expenses against your rental income as well. 

You want enough so that a potential law suit would go away if the insurance paid out.Best thing is to highly maintain your property and treat guests with respect so that no one would ever want to sue you.

Equity plus yearly return from cash until they are paid in full, for example?

Ideally, I’d like to become so much of value that I’d be paid for my help/ services.

Your market is expensive, I wouldn't look for normal working class people as your target customers.

Depending on the loan product, you may be able to exclude business debt once the business has paid the debt directly for 12 months.The income and losses related to the operation of the entity will affect the income side of your DTI (like Jay explained) if you own 25% or more of the entity.

After removing the expenses involved with turnovers, she is getting back a 1/4 of what she lost in that cancellation. 

Its dashboard is so cluttered, it hard to see who has paid and who hasn't.