Partyland

This shop goes crazy twice a year: Once around Rugby 7s, once around Halloween.
Indeed, if you need any reason to hang around Stone Slabs Street /​Pottinger Street risking of falling off miserably any other second, hunting for some good costume would be a good explanation.
Forget about Taobao or online shop. We (aka the party crew) constantly buy costumes here for quite a few years of Sevens and Halloween already, and the quality is always superior than the Taobao-​equivalent. You got everything covered here, from the old-​school pirates or cops, to the latest Avengers or Minions. Come with size too — I once bought a Snow White costume that specifically designed for men.
Heard you want props? Yes, you need props to party. Swords, glasses, wigs, wings, fabricators, masks, you name it. Quite abundance in stock too, which you can safely assume that you can buy the props in bulk for all two dozen friends in the party to make a matching theme.
Now two minus points.
One — the ladies were very, very reluctant to bargain. To a point that I believed they knew I needed the costumes badly (I did, as I had to wear them the day after), and they knew that they were sort of monopoly around, so they played the cards to the max. Apparently customer loyalty isn’t that important to them, as people only come twice a year.
Two — lack of costume renting. I got it, this is not their business model anyway, but I’d love to rent a Stormtrooper or other more polished costumes some time without spending 5-​figure on it, or rent a very seasonal costume and return it back, without wasting it at the corner at my home.
But if you look beyond these points, yeah, party time!