Somewhere in an old thread a pilot flying for a local operator or the owner (Heli Services if my memory is not wrong) posted that flying to China is not the problem, but the price for customs handling and paper work _per person_ is as a multiple of their hourly rate on the helicopter. I vaguely remember an example of HKD 56,000 for a person, but this is info that has been sitting somewhere on the back of my head for a couple of years. There are not so many HK threads on pprune, so I am sure if you look for it you will find it.
And I say it again: what Hong Kong needs is a Zeppelin NT !!
