Kudy k The Brown Kiwi Travellers Hostel

We're 2km from downtown and 20km from the airport.

Your most convenient and well-priced option is with a company called Supershuttle. They'll bring you to TBK @ $25 for one passenger, $31 for two, $37 for three passengers, etc. They have a free phone next to the information centre.
A taxi is around $40-$50.
A cheaper option for the single traveller is with the Airporter. It's $11 one-way and $18 return. Get off the bus at Britomart bus station.

From here catch the Link bus from platform 9, travelling in the anti-clockwise direction. Get off the bus at the Three Lamps stop which is the first one on Ponsonby Rd. Look for the BNZ (Bank of New Zealand); next to the bank is a walkway through their carpark. At the exit you can see The Brown Kiwi, a two-storey wooden villa with a flag pole out front.