You want something cheap that won't break...mmmmmmmm Hyper 7 PBS RTR.
Since you don't race the hyper 7 is a tank.
I have it for over 2 years now and haven't broke or changed anything on it.
I still got the hyper engine that came with it and it still runs.

Try ebay for good prices or order it from www.rcmart.com, or www.rc-mushroom.com.
Since you are from NZ buying it from US won't be cheapper for shipping.
Plus from Hong Kong almost all buggies are around 15% cheaper.