I have been out of the light aircraft scene for quite a while but continuing the discussion if you do go down the purchasing road (which I didn't) I would seek the opinion of a local Lame/maintainance provider before you go shopping.
The NZ GA fleet is fairly small so you may find a better option is to import from overseas but again your LAME will help steer you in the right direction.
If I was to purchase an aircraft I would aim for a four seater over a two seater for comfort and practicality. I have always considered the C182 an ideal aircraft for private flying in NZ but it's probably not ideal for ab-initio training.
If your determined to buy something to learn in, have you considered a C150/170 series syndicate? You will have some of the benefits of ownership with the added benefit of pooled knowledge and organisation assuming it is run properly.