I only know about the R22 which I can highly recommend, especially after having been to the factory safetycourse.
I was told if you were to own an R22 it would cost you something like £100 an hour to run it and if you manage to hire it to your training organisation it earns its keep.
Regards to making a mint in this rotary business I believe the young ones are flying Helicopters because they love flying and quality of life.
Now how can one put a price on quality of life?
Also do not forget you already bought all your toys, you already own your house and I imagine you own a car so all you need to earn is money for food and the mortgage.
And somebody is paying to fly helicopters which can be worth millions, with views which are priceless.
regards Brilliant Stuff