A vendor can only see specific feedback that has been left on their own products, not which user has left feedback on other vendor's stuff.I always try to keep track of the registered userbase. If a buyer comes to me with a bunch of transactions but a very recent user number, I will either insist they go finalize-early, or provide me one reputable illicit seller they have done business with that will vouch for them via a Personal Message. You'd be surprised how many just fade away. And since my scam-bells are ring-a-ling-ing at this point, good freaking riddance.