I would buy a cheap, basic dress from F21, H&M, Charlotte Russe, or those kinds of places and then customize it yourself. I did that for my prom dress (here) and ended up spending maybe a total of $40. For mine I just sewed on lace and an extra layer of fabric. Good accessories also help your dress a lot. From my experience, most people either don’t wear jewelry, or wear a plain necklace with an equally plain dress.
Hope this helped. Have fun at your semi!posted about 5 years ago