Since posting this I have found out a little bit of information about kite surfing in HK and comparisons to other countries.
For a 3 day beginner course to obtain your level 1 & 2 IKO certification it costs $4500. The courses are a maximum of 2 students per instructor.
Here are 2 locations you can go to kite surf depending on the time of year:
For the same 3 day beginner course for level 1 & 2, here are comparisons in other countries:
Kite HuaHin - HauHin, Thailand - 11000baht = HK$2,800
Isla Kite - Boracay, Philippines - 340€ = HK$3400
Kitesurfing Phuket - Phuket, Thailand - Semi-private: 11000baht = HK$2800 and Private 16000 baht = HK$4050