Someone's home? I've crammed 30+ individuals in my home before. Every one fit in a 650 square foot ish main floor. For 80 plus dance floor, can you have individuals on the main floor and a basement? I'm guessing in a suburbia home of 2200 sq ft, you have two levels of 1100 to host 40 people on each level.
Pay for catering and pay for a cleaning service afterwards?
If the extra curriculars are going to be too much for a friends home, there's always Air BnB...
One thing I didn't notice yet, for 80 people, parking is going to be a little bit chaotic no matter where you choose. But I think a community hall would have the least headache dealing with it.