Formal dress alterations cost $60 to $200, depending on the fabric and what changes need to be made. The most common dress alterations are hemming the length, taking in the side seams, adding bra cups, and shortening the straps. More complex alterations like adding a corset back or increasing the entire dress size cost more.
Delicate fabrics must be hand-stitched, and each dress layer hemmed separately, increasing costs. Chiffon, taffeta, and satin skirts require a labor-intensive rolled hem which takes more time and costs more.
Heavily embellished gowns also require special care and stitching. In fact, many embellished skirts are shortened from the waist to maintain the hemline design which requires a more experienced seamstress to work with the delicate beading.