Flint lived in Los Angeles, where he earned his law degree from UCLA, and had a family law practice for over fifty years. At the time of his death he was married to Joyce Flint, a former fashion designer-turned conservator, and had two sons, Michael, a film producer in Hollywood, and Guy, an educator. He also served as a Co-Director for Machal West, an organization composed of American Veterans who fought with Israel in the 1948 Arab–Israeli War. He co-founded the organization.