Hi,
2 weeks = 10 days :-)
This is a positive estimation. You may not spend that much money nor seeing or doing all the things that I've assumed.
The costs below is for both of you (see total cost all the way at the bottom):
Hotel room for couple (4 stars or higher) - approx NZ$200/night = NZ$2000
Fine dinners (1 night dinner probably $130 including reasonbly priced a bottle of wine and possibly you'd like to do it 3 times during your 2 weeks holiday) = $390
Other food cost (e.g. lunches, breakfast/snack, casual dinner) = $50/day X 10 days = $500
Clubbing (entrance fee and drinks ) and you'd do it for 2 nights ($75/night) = $150
Visiting famous natural or historical sites (say you decide to join one of those greyhound tours or catch your own public transport instead of hiring a car), Greyhound tour to 3 historical sites for 2 ($100 for both of you times 3 sites) = $300 plus any other entrance fee $150.
Total sightseeing = $450
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SO FAR cost for both in NZ dollar:
1. Hotels = $2000
2. 3 nights of fine dinings with reasonable priced wine = $390
3. Other food cost (e.g. breakfast/snack, lunch and casual dining) = $500
4. 2 nights Clubbing (entrance fee and drinks) = $150
5. Sight seeings = $450
TOTAL = NZ$3490 = AU$3017 = US$2742 = £1384 = EURO1756