From left:The vendor, the Beresford building and Jerry Seinfeld

It sounds like a plotline for an episode of “Seinfeld”: a group of well-heeled Upper West Side residents take on the hot dog vendor — with hilarious results. But this coop v. cart battle is no joke.

Residents of the Beresford on Central Park West — a stately co-op home to Jerry Seinfeld, himself, as well as to singer Diana Ross and tennis legend John McEnroe — are insisting that a hot dog vendor who has set up shop outside the exclusive building move his cart, sources told The Real Deal. [more]