It depends what you would like to have. Hong Kong now has most of international brand boutique available to consumers. Prices should be inline with other cities in to the world and now it is a summer sale season.
[[SPOILER]] Lai sifu did the same cutting to one of my jacket too when I asked for more open quarter. After that I am careful enough to instruct him to make a curveture.He is quite good to judge horizontal and vertical balance but I need to be more careful about curve and diagonal lines. BTW, The jacket looks comfortable and color is nice.
If you see them in person with multiples orders at a time, you may be able to ask some sort of discount if you ask nicely.
I think they would not give a discount on internet based inquiry.
You must be very lucky to get your suits spot on for the first try from both style and fitting point of view.
In the thread there are recent unhappy customers' report of Chan and Yao who commissioned suits with tight schedule.