Hi! Got to check out the 2nd hand market too around the area of champaign court near kimberly. Everytime I go to HK in the past two years, I return with a 2nd hand lens purchase. Prices are reasonable (you must do your research first and remember to bargain), but HK has more 2nd hand stuff to offer than singapore in my opinion. Some of these shops selling 2nd hand stuff are also where you can obtain some grey market stuff. Think there is a previous thread whereby someone lists the shops.