Thanks very much for the reply.  This organization is not churched related, it is a local horned animal club.

The ballroom was rented to members and to non-members.  The non-member rentals were not program related, they were personal in nature, baptisms, birthdays, and other events.  These private events were catered by private vendors, not by the organization...but the private vendors used the halls kitchen.  The rental fee allowed that.  I was only given last years 990 and there was no rental income reported as UBIT.  The ballroom has not been rented since 2019.

There are smaller rooms available at low rent for low income members but they are rarely used.  

Assuming the sale of the ballroom does result in taxable income, how far back does the organization need to go to determine what portion of the rental income was for members / program related...and what portion was for private / unrelated?  

Appreciate any information you can provide and if the exclusions I provided in the post apply to this scenario or not...I'm assuming they do not, but appreciate your thoughts.