One wise friend advised me to register on Heritage Auction's site in order to be able to search the history of what a coin sold for. For example I would search for 1938 5C MS65. It would give the specific graded coins and what they sold for. The benefit is seeing what graded MS65 and by which TPG.
I had tried using PCGS's photograde but it uses different years in the pictures. When you want to learn about a 1938 5C grading at MS65 you want the photo to be of a 1938 5C rather than another year.