You should be on the stage. There is one leaving in 10 minutes, be on it.
There is a big selling site over here. You buy something, and pay the site. They verify the payment and tell the seller, who has a limited number of days to send the goods by recorded delivery. They know you paid, the seller has sent it, and that you have received the stuff. You have so many days to release the payment, or trigger a dispute. After then, the seller is paid anyway. If sending or delivery doesn't happen, you get the money back from the site. The site has special price deals with a nationwide carrier for sending stuff as part of this process.
I had a seller send me a lower spec version of a piece of tech. I opened a dispute and the payment to him from the site was immediately frozen. I sent the site photo evidence and they told the seller to sort it so I was happy, because I was getting the money back from them if he didn't. He arranged for it to be sent back, and I got repaid by the site, although he did wriggle a little bit during the dispute.
Andrew