depends on how much details the dress carry...
and also whether it is retailed clothing or haute couture...it is of great difference
for retailed clothings, if summer style, with not much details (e.g. lace, embroided prints) and not deluxe quality (100% silk), 30k + is commonly seen
if winter style...40k-50k or even higher ...
for haute couture...can't tell...6 digits price is minimum...