Used products are NOT sold via "close out" sales. If you're buying used products for re-sale then you're a "used goods dealer" [or "secondhand dealer"] and must comply with all the local and state rules that apply to that industry.
As for you buying new, genuine products from a close out buyer and then re-selling those products that is [as you've already been told] sometimes lawful and sometimes not. If, for example, the products are repackaged or damaged then, no, you may NOT lawfully re-sell them as new -- perhaps at all or perhaps you can with an appropriate disclaimer.
You're looking for someone to tell you that all is well with your business plan. That's not going to happen -- not only because none of us serve as your attorney but because there are far too many variables to give you one set answer. One lot of products bought from Close Out Buyer may be lawfully re-sold. But another lot of products bought from the same Close Out Buyer may not lawfully be sold. Each transaction requires its own analysis. Your own intellectual property attorney can help you vet the Close Out Buyers that you want to purchase from and the distributors and retailers from where they purchase their products.
You're smart to be concerned about the pedigree of the products sold by close out buyers. If you re-sell products purchased from them, and the products turn out to be counterfeit, then YOU are monetarily liable for the infringement damages. And you may be criminally charged as well. Your due diligence investigation needs to be extensive. Good luck.
The above is general information ONLY and is not legal advice, does not form an attorney-client relationship, and should NOT be relied upon to take or refrain from taking any action. I am not your attorney. You should seek the advice of competent counsel before taking any action related to your inquiry.
You cannot get that question answered here, only receive general advice based on the limited facts you give.
Close outs do not include used goods, so something is amiss. Be very careful. There are some counterfeiters that survive for more than three years. eBay knows very well that much of their merchandise listings are counterfeit items, but eBay is still here and will be. They are careful to protect themselves legally with TOU, indemnities, warranties and can charge back or discontinue listings and even ban sellers if needed. That is quite effective, as most of the sellers want to stay on eBay and there are various "safe harbor" provisions built into the law to protect them. They have highly paid lobbyists and lots of money to spend to assure that the laws protect them.
You need to be very cautious and be sure the seller is sufficiently solvent to reimburse all your costs if this stuff is not authentic.
I am not your lawyer and you are not my client. Free advice here is without recourse and any reliance thereupon is at your sole risk. This is done without compensation as a free public service. I am licensed in IL, MO, TX and I am a Reg. Pat. Atty. so advice in any other jurisdiction is strictly general advice and should be confirmed with an attorney licensed in that jurisdiction.