@Nathan G. natural gas service, in Philly, is provided by the Philadelphia Gas Works which is a publicly owned utility service. 

The MLS that I use allows me to search public records based on building type(SF or MF) and wether or not the owner lives in the property of not.  

The Deposit to Hold removes the property from public offering and holds the home exclusively for the Applicant until all other requirements have been met.

The highest bidder is the one that wins the property during the auction conducted by the tax collector.Nothing is more important than conduct at these public auctions, seeing as how people could go to jail just for telling someone at one of these auctions to buy the current auction and let them buy the next.

So they tenant will be responsible for their own water/sewer/trash which is paid directly to our city public works department.  

there are at least 3 public reits that own towers that might buy it from you.

Has anyone had experience/success in contacting owners of properties that failed to sell at public auction, shortly after auction closes?

Your local circuit court will determine a day and time for the public auction.

That isn't publicly available. 

*Reforms Individual Apartment Improvements (IAIs) to limit rentincreases to substantial modifications:o Up to 3 times in any 15 years, for up to $15,000;o Amortize: 14 years for smaller buildings of 35 units or less; 15 yearsfor all other larger buildings; and,o Surcharges expire in 30 years.Part L: Requires the Division of Home and Community Renewal (HCR) toconduct an annual report on rent regulation that would be due on Dec.31 of each year and be made publicly available.Part M: Establishes the Statewide Housing Security and Tenant ProtectionAct of 2019."