The Okinawa Marriott Resort & Spa in Nago City, Okinawa, Japan is currently selling for just $112 on hotels.com.
To get the $84 rate, just book on Marriott.com (almost all Marriott.com non-refundable rates have 24-hour free cancellation) and apply for a Marriott Look No Further (LNF) claim. The LNF team will reply within 24 hours and make the rate adjustment.
Okinawa is a quirky, but beautiful place. September is still considered high season and it is warm enough to hit the beach. I was there in January 2015 and wrote an Okinawa guide. I enjoyed my time there, despite the somewhat coolish temperatures.
We found low rates for the last week of September 2015, but there might be more dates available.