Private feedback and private auctions should also bring up a red flag when it comes to any eBay transactions. Feedback portfolios are designed to show how trustworthy a seller you are. If you are hiding your feedback, you are hiding how trustworthy you are. I doubt there are many sellers with great feedback, that they don’t want others to see. Likewise, if a scammer is buying feedback, chances are he or she doesn’t want his or her buyers/potential victims to know about it. If a seller has a lot of private auctions, or private feedback, ask them why. If they don’t give you a good enough answer, don’t do business.