Vancouver has, in general, always been relatively pricey compared to other parts of the country. Vancouver, like much of the West, also is far more prone to large swings in the market due to commodities.
Unlike the Western USA, the Canadian West has never really diversified it's economy. There is still no real manufacturing base and nearly all head offices are commodity centers with no banks. Outside of oil there are few corporate offices and none of the 20 largest corporations have their head office in Vancouver, shocking for the nation's 3rd largest city. Western Canada doesn't have the manufacturing base of L.A. or financials and hi-tech of San Fransisco or Seattle. Interestingly the only automotive plant in the West is New Flyer buses in Winnipeg.
Due to the nature of commodities this can bring about huge fluctuations in the economy in very short periods of time. When I was a kid in the late 70s EVERYBODY was moving to Alberta for work and it looked like the good times would never end and needless to say they did and very abruptly. All of this is why housing in the West has always been a very up or down scenario. Again Manitoba, which is the less commodity based economy, never had the severe boom or bust cycle which is reflected it's housing price growth being more in line with inflation.