I have had a Kinek account for about 10 years and use their pickup location in Calais, ME. It is at a warehouse just past the old border crossing, near Marden's and the new Dollar Tree. They give you a unique mailing address and charge $5 US an item, no matter how big the box is. I have had car seats, long spoilers, side skirts, and other items that sellers in the US refused to ship to Canada, or were way too expensive to ship to Canada.
While I have only used the Calais location, they have locations across the US.
Shipping inside of the US is much cheaper than sending it to Canada. I have seen items that sellers wanted $500 to ship to Canada that they shipped free to the US location.
Here is the link to the Kinek website: https://www.kinek.com/
Kinek notifies you by email when your package arrives.
The only issue is that before you use Kinek, you have to go to one of their locations with your ID/passport and register for an account, and get a mailing address, which is free. So the first time down, you will not have a mailing address.
Here is a screenprint with additional details. Items on a pallet, like an engine, are $20. They do have a forklift on site.
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