As a seller, I can only remember one problem, and that was a Canadian trying to get me to mark the package as a Gift. I understand the reasoning, but I don't agree with it, and I refused. Never heard from him again. *shrug*
Lying on a customs form is a federal offense, and marking an item as a gift when it is in fact not a gift is a good way to have it opened and searched. Good for you for not doing it.
Another thing I learned on the ebay help center.
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