When online, they can show you any picture which are easily available with a Google search. What arrives in the box, if anything at all, is what truly matters.
An example just a few months ago, I posted a WTB in a FB group for car spare parts. One person PMed me he had the parts for a good price and sent pictures. As I had been doing a lot of Google already, the picture he sent looked so much like what I had seen somewhere online. To test him, I asked to COD and the person gave many excuses that he was far away and provided a Google location pin is a remote location in Kedah. I replied that I have a cousin living nearby only 45 mins away and can pick up. He went silent and blocked my number.
Unless you really know the seller, DON'T.
Of course not every online seller is a scammer and a few members here, myself included, have bought online from a US seller but that guy had solid references and a long history of online selling. Regardless, it was still a bit of a gamble, sending the money by wire and waiting the few days for the package to arrive and then taking it to the service centre for verification.
Anyways, when I asked for the Rolex warranty card, the overseas seller showed me a paper warranty card claiming to be a 2022 watch. If not mistaken, 2022's Rolex warranty should be in card form. Suspicious.. 
Sent from my SM-A525F using Tapatalk