If you are looking at this from an investment perspective, that may make your returns non-existent.

You do that, your biggest expense (mortgage) doesn’t exist.

If you want to look up the original article, which has links to sources and to other great resources, (I can't link as per BP rules) the article is called "33 Real Estate Statistics That'll Change Your 2019 Strategy" - by Mike BlankenshipGeneral Real Estate Statistics In 2018, 5.5 million existing homes were sold in the U.S. 

I COULD just have title pay off the existing crazy water bill then keep working to have Philly Water reimburse me, but I also have heard horror stories of getting the city to pay you back on something like that being difficult to near impossible to pull off once you've actually paid them.

Looking to be very organized on not only our tenants that exist already taxes ,rent and mortgage etc.

Seems a ten-year-old could have cracked this one by just looking up a few mortgages, to see if they even exist.

You may want to start off by becoming a co-host which is where you basically manage the business for an existing Airbnb host.

The various cities out here each have their own regulations restricting STRs and those regulations can and do change relatively abruptly.

It will depend on your state landlord tenant regulations regarding community rules which may or may not be the same thing as the lease.

Use some of the available tools out there to run high level analysis and then once you have a short list you can start engaging property managers, do more manual research on the existing booking platforms and/or pay for more expensive data to fine tune your analysis.Best of luck!