The Quilt Sofa // by Ronan and Erwan Bouroullec // How can I tell if its genuine?  

None of the photos are of...
None of the photos are of the actual example the purchaser would receive. Considering the listed price, surely the seller could have been bothered to photograph the thing. It's possible to see that all of the images used in the listing are from elsewhere after doing a Google image search. That, combined with the experience (or lack thereof) of the seller, plus the very generic description would make me inclined to believe that something is off about this listing.

Well
The "collection in person only" shipping means you can inspect the thing, eh?