I'll have a birthday party for my daughter in Feb in World Trade McDonald. If you are member, there will be 10% discount for the birthday party with purchase over $700. And there will be special offer for the member every month. I also order balloons decoration, $80 for a 6 feet tall balloon stand & $20 for a 3 feet balloon princess/prince. They are quite cute!
If you have more guest, you can go to Tsim Sha Tsui East, they can offer space for 60 person. I held a party in Hang Fa Chuen last 2 years, I also ask for more then 40 person and they gave me at last but the seats were separate.