I'd say that a re-spray will give a hard finish depending on the laquer used by the body
shop. Even if they used a SEAT base paint, if they used a 'better' laquer then the paint would be 'harder'.
But I can't understand why the guy would suggest that the rear window has been removed, when only the passenger door has had a respray....
Surely the door would have been removed from the car for the respray......