Around here, the "mitzvah's" carry a status premium that regular dances still haven't achieved.
These guys charged us $4000...the floor was packed all night long, and I didn't have a headache when I left the room !
It was a pro affair. I think the final bill for the entire prom was around $13,000.
Tickets were $200 per couple for students, and $50 for the teachers' guests. We had many fund raisers throughout the year to offset the cost, as well. We might have come close to raising about 8-9k, so that's not too bad for such a great party!

Too bad I'm not a better dancer !