7-8 unit, single building condo complex - Seller owns all units. Seller Finance.

[Butch Greene]

Rented a condo on a trip. Aged, cobwebs throughout. Outdated units. All their AirBNB reviews are similar.  Asked the owner if he'd sell & he immediately said he'd consider owner financing.  I have a friend who buys townhomes, not condos who is my only potential buyer. He's not interested in condos.
All units in the building are owned by the same party. I pull up all units tax links on GIS, but no data attached.
 
What are the hurdles to locating a buyer?
Don't know enough to price/comp it out. Don't want to say too much with getting it under some contract or protecting my right to a finder's fee.   Still haven't "done my first deal".