What short and long term goals you have in mind.   

The regulations are basically 1) You must be the permanent resident of the unit you wish to rent, 2) You must be registered with the City as a business and as a short-term rental, and 3) You may only rent 90 unhosted nights per year.

The short of it:Hey BP!

I'm open to flips, buy & hold, Foreclosure/REO/Short sale pretty much anything outside of section 8 if the numbers are right. 

I have had 3 applications. 1 had too much debt. 1 called shortly after applying saying they don't think they want it because it has a window AC unit and not central air.

A practice of nickel-and-diming me to death will not have great benefit for them because it will generally not result in handing me the short end of the stick, but also reduce their share of the rental income.

Until those houses are paid off, and they will be paid off much faster on 15s than on 30s, you are short cash flow.  

The rest will be difficult and undersirable no matter what, and I offer to let them free and off their lease agreement on the spot as long as they clean up my property and take all of their belongings with them but most cannot afford to move in such short notice.

The short answer is the financing depends on many factors; income/assets and credit of all partners or parties to the transaction on the buyer's side, operating income statement for the building, deferred maintenance, occupancy all come into play.Stephanie

Let them move along if need be - despite the short term pain it may feel like it is causing!