Reutrns if you sell in Canada

If you sell on the Canadian platform -- as opposed to allowing Canadian orders through the dot com site -- then you may not require those buyers to return outside of their own country. Nor must those buyers be faced with any sort of import/customs duties or fees -- so unless if falls under the collection threshold, you will not be able to use USPS but must use a carrier that allows you to prepay.

Selling on the dot com site and allowing international means the buyer is responsible for import duties.