Heitz Wine Can Someone Tell Me How Much The Bottles Of Wine Are Worth Or Where I Can Go To Find Out?

Can someone tell me how much the bottles of wine are worth or where I can go to find out? - heitz wine

We have 4 bottles of wine and wonder what they are worth. I know nothing about wine and I do not know the exact name, so I just everything I see on the bottles.

1. Moulin des Carruades ste Civil Pauillac 1974 Chateau Lafite-Rothschild, France

2. Napa Valley Cabernet Sauvignon 1976 Robert Mondavii Oakville, CA

3. Grand Cru Classé Château Duhart-Milon-Rothschild 1973 Pauillac, France

4. Heitz Cellar Napa Valley 1979 Pinot Black Saint Helena, CA