Whilst working as driver of a city sanitation truck in the morning, he trained in boxing each afternoon at a gym on Pleasant Street.
"[4] In his next fight, Costner fought Kid Gavilán, a future International Boxing Hall of Famer, and won in a controversial 10-round decision.
Over the decade from 1958 to 1968, Costner "didn't do much but take low-wage jobs and leave them", and "subsisted on a military pension, social security, and the notion that nobody has much use for a blind man."
At the encouragement of friends, he studied for a GED, then, with a 3.7 grade-point average, took an AA degree from Cuyahoga State College, in Cleveland, Ohio.
He went on to work for the Ohio Civil Rights Commission as an intake specialist, retiring in 1985 to his apartment "off Gilbert Avenue, listening to scratchy jazz on the radio".