Complex sentence: He choose to leave the business in 2004, selling the entire Saga Group (which included insurance and holiday businesses) to a management buyout for £1.35 billion, although he continued to run some of the radio stations himself.
Split into simpler sentences: He choose to leave the business in 2004, selling the entire Saga Group (which included insurance and holiday businesses) to a management buyout for £1.35 billion. Roger continued to run some of the radio stations himself.