Note: This was brand new construction, with possession around early next year.

Whoa, whoa, whoa there pauly;The "deed" isn't something that you "possess".

It gives the buyer possession of the property.

I am seeking to connect with investors who possess firsthand experience with the Philadelphia Sheriff's Sale.

Also known as possession of property if the taxes don't get paid back after the state set amount of time.My question is, does the state deem that "amount of time" as counting from the moment YOU purchased the lien or from the moment THEY issued the lien?

The first lien holder (bank or other corporation as you mention) isn't going to let you foreclose on the place.Taking possession of a property like that is going to invite a lot of work and headaches on your part.  

You need to find out what you possess then market that ability to those who need it.

Try and get the tenant to leave and return possession willingly, signing off on a lease termination.

The risks for the seller in #1 are buyer default, the costs of foreclosure (or deed-in-lieu, if that makes sense), and, if the property ultimately becomes yours again through the foreclosure process, the costs of obtaining possession plus any damage to the asset.

I would just let them out of the Agreement, charging for every day of occupancy, and cleaning/damages based on conditions found after they turn over the keys and possession.