Since it sounds like your from a State that doesn't register and title truck campers it is a lot easier. Above advice is spot on. Definitely declare the amount of money you are carrying. Bank cheque plus what's in your wallet. Bring a copy of the truck camper ad. Even if its on Craigslist or whatever, have something. The amount of money is going to make the border guard ask a few questions but it should be no issue going through if you answer all questions clearly and without hesitation. Don't hide anything. If they ask a question your unsure about just say your unsure.
Since its a private seller get a written Bill of sale from them. Signed by all parties. Addresses, names, etc. The border services are going to want to see this. As for paying duties to bring it home. "Probably" not. Every time I ask when I go in to check on this, this is the answer I get. They don't want to give a clear answer as they are unsure of what your bringing back until your there with it for them to see.
Yes you have to declare the truck camper.
I had a truck camper for sale in Canada last year with interested parties contacting me from the US. I went in and checked about having the camper going South with a new US owner and the above info was what I was told.
To be sure, on your way to go and get it stop in on the US side and ask what it takes to bring it back. Then you'll know for sure about what your in for on your return trip at that particular crossing.
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