I attribute Aucklands increased house prices to chinese immigrants and printed money (ie, low interest rates) flooding the global economy.
People don't like pointing at the chinese, but clearly the chinese population in Auckland has dramatically increased. I remember the time when the queen st arcade parlours were filled with maoris and european kids ...at some point around 1993'ish the asians started outnumbering the locals and the demographic changes have accelerated if anything.
I've lived in a few western cities around the world , and Auckland is not the best by far. There are some nice things, the eastern suburb beaches, north shore coast, pleasant harbour, but, really Auckland is quite a shabby little city with poor quality housing and awful traffic. Aucklands awkward geography ensures it's small population clogs up the roads.