Tricky one really, depends upon what you are using one for and where in the world it is.
I have owned / run them for over 10 years, tend to be very reliable, but here is a quick run down for a UK based one.
Insurance £ 9000 to £ 14000 on £ 250k hull value with betterment and xs bought out ( £14 k is for any puropose )
Annual inspection £ 2500 plus retification
100 hour / 6 month inspection £ 600 to £ 1200 depending if compressor needs inspecting.
Fuel 25 imp gallons / hour
Component costs are what they are - use MD's component reserve figure, suggest you add a bit as things do not always last, espically if the machine flies as a private one. Eg blades leading edge erosion strips.
Worst ever year running one £ 32k on 250 hours, but this included 2 new main rotor blades and FCU. But insurance at the time was £ 6500 and fuel was .15p per litre !!!!!!!!!!
You will not have more fun in any other type of helicopter. Given the option buy a low skidded D model, the best of the type.