here are few tips you should keep in mind

 The celebrity party dresses are usually on loan from the designer. These dresses are very expensive, usually cost tens of thousands of dollars. The world of celebrity is different from that real world of us. We rarely see celebrity dresses on sale unless it is to raise money for charity. We usually see wedding gallery sold at auction at vast sums of money. When you buy celebrity dresses, here are few tips you should keep in mind.
Authenticity Always check for authenticity. Generally, this comes with doing a little bit of research beforehand to make sure the celebrity actually donated the item to the specific place you are purchasing it from. Most celebrity dresses come with some sort of “Certificate of Authenticity” that includes an autograph from the celebrity and a picture of her wearing the dress.
 Repairs Celebrities are human, so dresses become to and snaps fall off. If you’re buying special occasion dresses from a reputable dealer or auction house, they will let you know about the damages before you purchase the dress.
Size Again, every reputable store and auction house is going to let you know the size of the dress before you make your final purchase.
Retu policies Be sure to check out the retu policy where you are buying the dress. This is helpful just in case the actual item looks nothing like the picture, or you develop a serious case of buyer’s remorse, which is understandable when you’re plunking down $50,000 for a dress. After all, they are not cheap discount wedding dresses, they cost you much money.