Even if he gives it, back the jerk will probably bad mouth him or his business anyway. Most believe Kevin shouldn't keep the money.
However, most also acknowledge the client is being a jerk.
Tell you what...I've got an idea that will satisify all arguments.....Kevin M can send me the $400. Problem solved.
Send it to
PA Krew
(c/o The "K"-Train)
House of Pain, Suite 101
Philadelphia PA 99999
(and for anyone reading who isn't sure, I AM joking)