Casablanca Style 1769 Comfortable unclassified dresses

I'm looking to sell an unused (tags still on!) Casablanca gown style 1769. It's a beautiful and super flattering gown but I purchased it before my fiance and I settled on the "type" of wedding we were having. It's a little too formal and fancy. I realize that I'm obviously not goign to recoup what I spent, I'm looking to sell it for less than what I paid. Thank you!