I has been my understanding that once the bank takes possession, they have a pretty strait forward system of getting them back to market.

You likely need to serve notice (which can be done in some cases before you close) then you need to wait the required time and then you can get possession or have the sheriff escort them out of your property.

Legal issues and other circumstances have led to my family holding possession of the property despite most of the demolition having already occurred.

"For purposes of enforcing the due-on-sale (or due-on-transfer) provision, if any, in the security instrument, theservicer must consider all of the following situations to be a transfer of ownership:- the purchase of a property “subject to” the mortgage loan,- the assumption of the mortgage loan debt by the property purchaser,- any exchange of possession of property under a land sales contract or any other land trust device, and- in cases in which an inter vivos revocable trust is the borrower, any transfer of a beneficial interest in thetrust."

This takes a while so you may want to get that started before the 30 days is up.Order a lien sheet to see what bills are due for you to record you deed.Record you deed.If it is occupied you either need to do cash for keys or file for a writ of possession.

You need a judgment to get possession of your property. 

You need to send a Demand for Possession for Non-Payment of Rent.  

Again, I don't cherish the concept of paying the premium that long, it feels like I'm throwing money away.I'm not quite sure if I follow what you are saying.

It could be argued that since it is vacant no one has possession.

I had a tenant apply, but he told me he was charged with a felony for drug possession in 2018.