You do that for everything you ship abroad. Whether or not the receiver has to pay will depend on the declaration and its value.What's the current deal with shipping cross border into the states? I have received packages via USPS without having any duty charged, but when I just shipped with Canada post I had to fill out a declaration with values for customs.
The best option I found is paypal shipping tools. I have a venture one as well but I found this to be cheaper and much easier to use than Canada Posts shipping tools. You can use Paypal shipping without ebay but you have to go to the link directly:
https://www.paypal.com/us/cgi-bin/webscr?cmd=_ship-now

Before, you were able to take payments with EMT and then use a special Paypal Canada Post shipping webpage independently. This also gave a small discount over regular Canada Post fees. I used it all the time, but now it is either shut down or buried somewhere in the website.Any time you get paid on paypal you'll have a create shipping label option at the bottom. Netparcel is cheaper sometimes though
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