Newbie and Full Gut Rehab

[Naskat Williams]

Hey, I need some advice asap! My great great uncle left his 2 story building, which consists of a store front church, and three rental units to members of the church( my family). The building has sat for some twenty years and now the city wants to demolish it. The city told the church that they either have to fix up the buliding or sell it, or they will demolish it.
The buliding needs a full gut rehab, and I am a newbie investor.
Here are the problems:

The lien holder on the house illegally sold the building to another owner, by posing as the reverand of the church. Now, my aunt's lawyer can not find the lien holder and is trying to get the deed back in the church's name. There was no reverand of the church, becuase he died years ago.

The building is in a neighborhood on the edge of urban revitalization, and there is new constrution up, and most of the buildings on the street are being gutted and rehabbed.

My aunt's real estate agent found a buyer who want's to pay my aunt $65,000 for the building and pay off the liens. However, the land itself is worth way more than that, we are taking about NYC! The land itself is worth $200,000.

So, now the entire family is fighting over money, and telling my aunt to take it. But, I asked her how much she wants, and she said atleast $100,000, and I jumped up and down.So, I figured I can pay off the liens of $25,000 and the purchase price with a rehab loan. I am even thinking of moving in and using the HUD 203k program to rehab the building.

How can I remedy this situation?I don't know anything about doing a full gut rehab, because I am a newbie. But, this property fixed up is worth atleast $600,000. I need help asap before they tear this thing down.