I knew that Cosmo Kramer was based on a real person but I didn’t know that they were almost exactly alike!(In mannerisms, not looks mind you.)
Prior to serving as Cosmo’s model, Kenny had a long career as a stand-up comedian and was the manager of a British reggae band. During the disco years Kenny created an electronic jewelry item that sold so well that Kramer was able to live comfortably long after disco died.
For six years Larry David lived across the hall from Kenny. One day Jerry Seinfeld asked Larry for help creating a TV show. Jerry became famous, Larry became George and Kramer became Kramer.