How much is a 1988 proof set worth?

The United States 3 piece Congressional Proof Set consists of a $5 gold coin, a $1 silver dollar (90% silver) and a half dollar, composed on 92% copper and 8% nickel.Current selling price is between $300 and $400, and is dependent on spot gold and silver prices. (Price shown is for $18/ounce silver and $1,100 per ounce gold.)