If the feds do as they have said ( libs or cons) there will be somewhere between 1 and 2 million immigrants over the next 5-10 years (200,000 to 250,000 /year) . A good bet is that 1/3 will settle in Ontario. So 300,000 to 600,000 mostly in the the Golden Horseshoe. taking a guess at 3 people per family thats 100,000 to 200,000 houses/condos/apartments PLUS the internal growth of people growing up, leaving home, buying a house. Minus deaths, leaving the province, downsizing to the exurbs.
Allow for thre green belt reducing the available land INSIDE the commuter belt...but allow for improved GO making longer commutes possible.
Allow for intensification in Toront itself which could add many '000 dwellings.
Allow for current relatively poor/new/whatever immigrants "moving up" as they historically do on a generational basis
So even if you half those figures... a lot of people have to live somewhere and Miss/Brampton will be on the preferred list
I think that house prices in the GTA/Golden Horseshoe will continue to outpace the rate of inflation unless something stupid happens to monetray policy and interest rates go up ( mortgages at 10% again)