I concur Fatphil.
I remember reading that the Spaniard who owned that house had been warned not to extend the building but had ignore the warning, He was given a deadline to demolish it himself but chose to ignore the order, So the authorities did it for him and he had to pay for it as well as a fine.

But Jools has already said that the  so-called "Estate Agents" are telling people all sorts of "terminological Inexactitudes"  (with apologies to Churchill  :)). It would appear that Jools is right. There should be some form of  licencing required in order to be an estate agent and buyers should make sure they don't forget their brains in the airport when they come over.