You could get an extra 10% off with Member Prices and collect a stamp for every night stayed. Collect 10 stamps, get 1 reward* night.
If you want to give your credit card some exercise, head out to Wanda Plaza Wuhai in Haibowan District.
If you're planning a bit of sightseeing head to Shizuizi Ruins— just one of the monuments in Hainan District.