bigbromski - not if you are selling it under the pretense that it was a gift and you can not attest to the authenticity of it.
It's completely fair game under that context. If you try selling a product and have misleading details about it such as "authentic louie votton (however the hell you spell it) purse w/ certificate of authenticity" and if it turns out to be a fake and someone calls you on it, then you may be grilled.
Or even better yet! You should just find some knockoff company of a product and write exactly that in the details. but just tell them as much as they need to know.
For example, put this in the headline:
"Authentic rollex watch"
Now let's just say that there is actually a knockoff company called ROLLEX and not rolex - the real watch manufacture company. Nothing you have put in your information is innacurate, because you do have an authentic ROLLEX watch. Now, whether or not people are stupid enough to confuse rollex with rolex is not your responsibility.
Sure you just may have someone try to take you to court. but as long as absolutely nothing you put in the comments were innacurate or 'purposely' misleading, then you probably have one hell of a case against him.
But sure, the original arguement of saying it was a gift may not be the strongest.. especially in court. Figuring that the prosecutor may just ask you who it was that give it to you as a gift. Which is why I may be a little bit more careful about wording it.
But hey, the majority of lawyers straight lie in court every day and get away clean, so you can always aspire to that
Anyways, I don't advise swindeling, hustling, or conning people out of money. But if you are broke and need some fast cash... ;p