SAMMAMISH — Authorities say a man killed his parents at their Sammamish home and lived there for five days before killing himself when police arrived to check on their welfare Tuesday. The King County Sheriff’s Office says 34-year-old Matthew Ficken may have killed them because he didn’t want his them to sell the house and move. The King County Medical Examiner’s Office identified 68-year-old Lorraine Ficken and 72-year-old Robert Ficken as homicide victims Thursday.