Expedia has 352 hotels and other accommodation options a few miles from Kadena Air Base.
Yes! Most hotel room reservations are refundable provided that you cancel before the accommodation's cancellation deadline, which is usually within 24-48 hours of check in. If you have a non-refundable reservation, you might be able to still cancel and be given a refund within a 24-hour period of your booking. Enter dates and click on "Search", then use the filter option "free cancellation" to get the best deals available in Kadena Air Base.
Study the collections at Yachimun no Sato, Sakima Art Museum or Yomitan Museum of History and Folklore. Sights like Nakagusuku Castle, Yamuchinnosato and Zakimi Castle are landmarks to visit in the area. Spend some time wandering around Chatan Park, Southeast Botanical Gardens and Okinawa Comprehensive Athletic Park.