There are some identifiers that some, hopefully all of us who know of them, will not disclose. This may sound like BS, but it’s the only way the few of us who are keeping track of what pops up is not a forgery, and the forgers don’t get educated and learn how to get around the identifier(s). It is not some super secret things they are very subtle identifiers.
I had someone come into buddies store and ask how he could have his MR lower remarked HK 416 D SF shortly after @4CDragon listed his 2 on GB!!
Now just think about that, why would someone want the SF markings besides to try and scam someone. I kindly told him nobody and even if you do there are people who will point it out right away.
So the scammers are alive and well!!