Check out the above thread. There are also many more on jobs and living expenses on this forum for Toronto vs Vancouver. Can't comment on business opportunities as that needs to be very specific and varies from province to province. Google is also your best friend to read up on taxes, import/export, demographics, etc.
I have been in Calgary for almost 8 yrs now and I love Calgary. Economy had been bad but picking up... Big city with small town feeling....Housing prices comparitively lower and more affordable.
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