I live in Vancouver and would like to purchase the above. I would like to know:
1) Where is the cheapest/best place in Canada to buy this camera?
PhotoPrice is your friend:http://www.photoprice.ca/product/03868/Canon-EOS-5D-Mark-III-price.html
It compares all the prices of US stores to Canadian stores including tax & shipping. (Make sure you set your province to 'BC')
Looks like cheapest for warranty (non grey market) is Adorama shipped to Vancouver for $3380.05 incl tax.
Cheapest Canadian is Aden shipped to Vancouver for $3665.03 incl tax.
2) Is it better to drive across the border and purchase from the USA (eg have B&H deliver to a UPS in Washington state to pick up?
If you plan on declaring it at the border -- you will have to pay tax anyway. The only thing you save is about $20 of shipping as shipping to the US is free and shipping to Canada is about $20.
If you don't plan on declaring it at the border you'll save the HST.