Man, that is one sweet little ship. So well done too.
That's it's main drawback Larry, it's really quite small. Ideal for one person longer term, fine for two for a day trip, tight for two over the longer term. A 26-28' version would be better for two people.
Think it possible the broker screwed the ad up? That's one efficient boat if it can get from Europe to the canaries on 260 gallons.
Looking at the listing, the boat has what looks to be a pretty generous sail plan. Every Colvic Watson I have every encountered was a motorsailer, in which case, that cruising range is easily within the realm of possibility.
Size-wise and design-wise, it loosely resembles a Fisher 37 which weighs 14T, has 80-100HP and carries 100G of fuel. They have larger sailing rigs, but also motor-sail frequently in lighter conditions. These designs routinely cross oceans.
Interesting vessel. Looks best suited for a colder climate with no outside seating except possibly on the cabin trunks. The only thing I'm particularly curious about is the decoration on this outside hatch - what am I looking at?