Complex sentence: Durst went on to become a real-estate developer in his father's business; however, it was his brother Douglas who was later appointed to run the family business, which is reportedly worth about $650 million.
Split into simpler sentences: Durst went on to become a real-estate developer in his father's business. However, it was his brother Douglas who later was appointed run the family business, which is reportedly worth about $650 million.