A man charged with murder in the stabbing of a Honolulu real estate agent whose body was found wrapped in a carpet in the driveway of her Makiki home, has pleaded not guilty.  Forty-one-year-old Vernon Baker's bail was set at $200,000. The Honolulu Medical Examiner says 58-year-old Mary Beth San Juan died from multiple stab wounds.  Police say the motive was robbery.