Conversation so far:
What was the inspiration for the character Cosmo Kramer in the show Seinfield?
The character Cosmo Kramer is loosely based on comedian Kenny Kramer, Larry David's ex-neighbor across the hall.
Was Cosmo Kramer always known as Kramer in the show Seinfield?
Cosmo Kramer was originally called Kessler to prevent legal issues since the Seinfeld character was based on writer Larry David's real-life next-door neighbor Kenny Kramer.
Why was the name Kessler changed to Kramer?
Kenny Kramer apparently liked Seinfeld. He permitted Larry David, who was the writer of Seinfeld from seasons 1-7, to use Kramer as Kessler's name.
Did Kenny Kramer do anything significant in response to the show Seinfeld using his name?
Kenny Kramer has been the host of Kramer's Reality Tour and Kramer's Reality Road Show since Seinfeld was on the air.
Was Kenny Kramer's  Kramer's Reality Tour successful?
As it stands, Kramer’s Reality Tour, Kenny Kramer's Seinfeld-based New York City tour, has been running since 1996.
Are there any other interesting aspects about the Cosmo Kramer article?
Michael Richards who plays Cosmo Kramer in Seinfeld did not in any way base his performance on the real Kramer, to the point of refusing to meet Kenny Kramer.

Question: Why did he refuse to meet him?
Self-contained rewrite: Why did Michael Richards refuse to meet Kenny Kramer?