Not only is it a huge time-saver, but those seamstresses will have likely worked with your specific dress before (or similar styles by the same designer), and many shops will give you a small discount for doing your alterations in-house
Size XS: Length 126.5cm, Bust 87cm, Waist 69cm, Sleeve Length 48.8cm
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Whimsical prints and bright colors are two other must-try trends
Step out into the night in this fabulous maxi dress, crocheted from head to toe
If the total length of all of this is over 7, or if you feel more comfortable with more info, You could have another point down from the underarm seam as a reference for how much you took out of the back piece