There are other ways to determine rental amounts like researching in zillow and/or rentometer, which I typically reference.

Scenario 1 they don’t or refuse to move- eviction costs and/or lost rent Scenario 2 they move out and Cap ex and turnover costs, lost rent, advertising for new tenants in a somewhat of a qualified tenant shortage, headaches can be avoided by simply having a conversation with the tenant to see where their head is at, and that they understand what your expectations are.

That's why we require clients to spend a couple days with us in Milwaukee up front, so we can get on the same page and determine an asset quality.Hint: the hood looks much better on a spreadsheet than up close in person.

It's simply overwhelmingly nuts. 

Determine if the area can support new construction.

Sellers apply market cap rate to their in-place NOI to determine their ask price.

You’re simply using some of the money you’ve already saved for your purchase to show the seller you’re committed and serious about buying their house.

.- If you're going after a seller finance deal I think once you understand what it will take to get to a finished state its simply a matter of aligning your needs as far as short term cashflow with the current rents/situation, with the net number the seller needs after the refinance.  

I've tried to give them the benefit of the doubt, but they do not learn from their mistakes and simply bury their heads in the sand.

Yes, when there are multiple adult occupants, you would typically combine their gross incomes to determine if they meet the income criteria.