The seller has the two lots legally separated, but due to deed restriction imposed by the subdivision development, found that building a house on the “tennis court” lot was not allowable. 

What documents do they require, what credit scores do they allow, how do they verify previous rental history, etc.?

Bank of America does this - not sure about the minimums, but if you have a good relationship with your local branch, they can waive the monthly fees until your balance grows from rental income.

This would allow for a longer carry back with up front cash flow.

I bought about 65 homes over that two year period.. did very well.. 

Paying this off is the start of learning how to invest and live well.

What if the smell was coming from a broken sewer line that was back-gassing into the unit, as well as leaking all around the foundation and rotting wood beams.

Well-maintained homes: Homeowners tend to spend more time and money maintaining their homes, which contributes to the overall quality of the neighborhood.

Scotia Bank in Costa Rica will allow you to open up an larger account as 'business owner' if you own your properties in an LLC but the process of opening an account is much more difficult. 

It does sound odd to me that there are no inspections allowed.