Do you need a tailor (someone to make you suits/shirts etc), or do you need a alteration/repair store?
If it's the former, you should try NampoDong. There is one that claims to speak English - never been, but see the sign from the bus. It's on the street that goes toward ToseongDong/DongDaeshinDong opposite Lotte Dept. Store (T-Water is on the corner) Alternatively, hunt around Nampo as there are many tailors.
If it's the latter - they are everywhere and should fix just about anything.
There's a tailor on Dalmaji in Haeundae. If you get off on the Jung dong exit at the end of line 2, you can walk about 10 min or take a 2k won taxi ride to it..Not sure of the name but it is directly in front of the City mart (pronounced Shitty martuh)lol...It is just a little up the road from Mexican Chicken and the waffle house. If you come out this way just call me and I will guide you to it. The guy doesn't really speak English but he can help you. Good luck!
The store is white and blue.
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