I've been MOB on two occasions. Both times I bought my dresses from clearance online, paying $70 for each. I bought one from Chadwicks.com, also try ColdwaterCreek.com (clearance sections!). I don't wear sleeveless or low front, low back dresses which makes it harder for me to find things. But generally have had good luck with online clearance.
Oh, and also try on your shoes before the day! I bought this gorgeous pair of shoes online and the morning of the wedding put them on for the first time...they fit, but kept falling off my feet. As you can see in the picture, I'm wearing black strappy sandal shoes I borrowed from my daughter!
$70 Coldwater Creek clearance dress
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