The most expensive royal wedding dresses Grace Kelly’s wedding dress cost $65,200 when she married Prince Rainier III of Monaco in 1956, which would be $623,000 today. Grace Kelly wedding.Designed by Helen Rose, Kelly’s dress used 400 total yards of ivory faille and silk net. Previous Next Pages: 1 2 3 4 5 6 7 8 9 10 2021-05-07 spiel