I am moving back to Canada (where I am a citizen) from the United States (where I have been working for two years under TN status). I have been planning to ship the majority of my personal belongings to Canada using the United States Postal Service. When I went to the post office with the first package, they requested that I fill out a USPS Customs Declaration and Dispatch Notice (PS Form 2976-R, April 2016).
This customs form seems to require an itemized list of everything I'm sending, with weight and cost for each of them. This would be an enormous pain. The boxes contain everything from disorganized bags of lego and trading cards, various personal electronics, assorted clothing, books and magazines, cookware, sports equipment, and other things. I do not know the value of most of these items, and some may not have a clear specific value. (Although for what it's worth, all but a few are individually not very expensive.) I also don't have a postage scale (I was intending to use the one at the post office to weigh the boxes in their entirety, not expecting to need to weigh every item individually), though I could buy one if required.
Is this actually necessary for shipping existing personal belongings to myself?
I understand that such declarations are necessary for sending new items as gifts, or items that are being shipped for commercial purposes, but it doesn't feel correct for simply moving my own possessions from one location to another.