The screenshots do all appear to be from the same monitor (the bezel looks the same) but yeah the high cost of a trashed 800 with an incognito in it to cover "the very high ebay fees I have to pay for a sale" which they mention three times is laughable.
The fact they mention "Some cracks in the casing have been fixed and it's structurally sound." but show no pictures of them, I'd not go anywhere near this.
20 quid shipping for an 800 is way too low for something so fragile, they probably got it cracked because the psu smashed into the 800 in transit and they are going to use the same level of care shipping it back out again. "No returns"... nope!