Black tie attire is costly, no doubt about it, and while you might be able to find a great deal, shopping around will take you time. If a new ballgown isn't in your budget, we have two ideas. First, ask around. Chances are you have a friend with a dress you can wear just hanging in their closet that they'll gladly let you borrow.
Second, there's Rent the Runway, which is truly a budget fashionista's best friend.
How Can I Look Fab Without Spending Too Much?