Potential huge wholesale - HELP!

[Daniel B Trader]

I'm driving out of town today for work and I see what looks to be a huge vacant apartment complex. I drive around the property, and after realizing how big it was, thought maybe it was an old assisted living facility or hotel. 

Regardless, the address wasn't visible, so I called the realtor across the street who said it used to be an old hospital. 

I was referred to a lady in the redevelopment dept in city hall who gave me the owners contact info and a brief history: vacant since 2008, property consists of 12 parcels that were acquired for 300k in 2013. The hospital itself consists of 2 parcels. She also mentioned she thought she heard about possible tax sale 3-4 months ago but never heard about it again. 

I called and the owner wouldn't give an asking price, just that they have 2 realtors eager to list it but they want to sell now. Have taxes owed. They have the 2 hospital parcels available + 8 additional parcels which happen to be surrounding parking lots. I said I might be willing to put it under contract as long as they gave me 90 days to cash them out. She said to send in an offer...

...ha NOW WHAT?!