Newzealnd itinerary help needed 10 nights

If you bus to Rotorua, have a kook at both Intercity a d Naked Bus. Have a look at their fares from 6 to 8 weeks ahead.
I would also consider staying near the airport and going from there. You would catch the local bus to Manukau Shopping Mall and picking up the bus service from there.
We recently used Naked Bus to go from Rotorua to Manukau City. Paid $4.98 each. IThe local bus to the airport from there is $5.50 each. Provided you book ahead, you will be able to get cheap fares as well. Plus its a pleasant bus ride.

Yes sure. Will check their websites. Hope to get the discount :)

The end of the trip may need changing. The train leaves greymouth at 1345 and gets into Christchurch at 1805. So you can hopefully find a bus from Franz to greymouth, but can you find a plane to auckland and time to get to the airport?

You'll have to look into this . but otherwise I think it looks doable although very hard work. And no driving so you can see the views.

"Want to cover both places" - LOL - which "both places"?
You need to slow down & relax. QTN to FJG is too far to drive in one day - OK in a bus with a professional driver.

Both islands, I assume.

I am suggesting a no driving itinerary which will hopefully work.

then how can i ctach auckland flight if i reach late?

What time does your flight depart Auckland?

25th morning 8am

You will need to fly to Auckland the evening before. Stay near the airport--do a search for close-by hotels.

Hi,
I have no experience with NZ but I am planning on my trip to Australia and I think the tool I used might actually be helpful for you too. It is a trip planner and it is very useful when planning on an itinerary :)

Here is my trip to Australia so you can see the final look http://triprepublic.com/trip/visit-the-kangaroos/public

Have fun on your trip!