I believe this is a juvenile showing faint streaking across its breast. This species was introduced into New Zealand from Europe starting in 1862 with initial introductions totaling fewer than 100 birds. It is now fairly common in settled areas although distribution remains patchy and numbers variable. The subspecies that New Zealand birds belong to is uncertain but probably one of the British or Northern European races: C. c. harrisoni or nominate chloris. Canon PowerShot SX50 HS.
References:
Angus, D.J. 2013. Greenfinch. In Miskelly, C.M. (ed.) New Zealand Birds Online. www.nzbirdsonline.org.nz
Clement, P. & de Juana, E. (2017). European Greenfinch (Chloris chloris). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. (retrieved from http://www.hbw.com/node/61334 on 6 April 2017).
Clement, P., A. Harris, and J. Davis. 1993. Finches and Sparrows: An Identification Guide. Princeton Univ. Press, Princeton, N. J.
Higgins, P.J.; Peter, J.M.; Cowling, S.J. (eds.) 2006. Handbook of Australian, New Zealand and Antarctic birds. Vol. 7, boatbill to starlings. Oxford University Press, Melbourne.