50-75K expenses? For a congress? In the US? Are you joking? The sound system rental alone is 15K. The floor rental is 8-15k depending on how tough the negotiator is. The hotel will not bill for ballroom rental if the hotel room quota is met.... but they do bill for everything else. There are also billing and credit swipe fees, security company, transportation company and so on.
Oh and let us assume it is all NON-UNION! I would be shocked if downtown SF is non-union. Most downtown hotels in most cities are 100% union.
The location is not in downtown SF. It is very close to the airport. There was very little union labor involved. During the first two years, it was volunteers who were installing and uninstalling the floor. I don’t remember how much the floor rental was. The sound system, lights, and stage were provided by the same vendor. If I recall it was about $10K or less.
My $50K to $75K didn’t include the stage, sound, lights, floor rentals, etc. These are fixed costs. I was referring to $50K to $75K for costs of hiring DJs and the “artists” which would include travel and lodging.
I went conservative in total attendees at 2,000. I know the number was higher last two years. The average of $100 per head (across those who sign up for party pass, full pass, daily drop ins and performs pass) is also very conservative.
Security is provided by the hotel and included in the ballroom rental. Like water refilling, clean up every day is also included.
Hotel is not providing transportation. Any transportation is volunteer driven. That I know for a fact.
Hotel doesn’t offer any payment or billing. For the rooms people pay directly to the hotel. As a LLC, the congress has its own direct square or similar account for credit payments. I doubt their rate is higher than 2.5%.
It can’t be denied that the SF SBK overall makes tidy profit. First year goal was to break even and not go into the loss. They key organizer looking after the financial aspects is savvy with business and not an “artist”

in year 1 and 2, the accounting was handled by someone who was a CFO of public company.