I bought curtains in Mongkok for my living room and bedroom for HK$1,680, including rail installation.There are several made-to-order curtain shops in Mongkok, particularly on Shanghai Street and Fa Yuen Street. I settled with Season Curtain Limited. Their address is:
182 Fa Yuen Street
They are open from 10AM-9PM.
They do not take credit cards.
They were a bit cheaper than other curtain shops in the area because the width of the curtain was shorter, allowing me to still close them but not with a lot of slack for ruffles once closed. Rods for my curtains would have cost extra so I went with railings.
Two days later, a guy came to install the railings and within a week the curtains were ready for pickup. Here’s the end result: