Fix transportation and you fix half the housing issues. Build 24/7 regional train links to Barrie and Peterborough and Guelph, and build streetcars networks within them, and suddenly they are closer to downtown then Scarborough or Mississauga.

Have the government do more to build their own non-market housing, create programs to make it easier to build co-op and community housing, and penalize housing market 'investors' who add no value to the economy, and you'll fix the other half.