I'm slightly confused by this concept as well. I'm looking at (4 nights, 5th night free) at the Marriott's Ko Olina Beach Club. The rate for the standard guest room is 120K. If I want to upgrade to a 1 bedroom villa the rate is 145K eCertificate plus 1 upgrade certificate required per night. Does that mean I can't book this room if I had 145K points because I would also need 4 upgrade certificates