We're planning to stay there in March. The lowest rate I've seen is 800 HKD advance purchase. Has anyone paid their advance purchase rate and do you remember whether they charged your CC before arrival? Some hotels don't, even on prepaid rates, making it possible to use the Costo certificates at check-in.

If I can use my Costco certs then I'll switch to the 800 HKD prepaid, otherwise I'll stick with 900 HKD flexible.