[raulus]

You mentioned the condition, but my experience is that often condition isn't a big factor for these pieces, simply because there's so few of them, and most of them aren't in top shape. It doesn't help that PSA grades them all as Authentic if they're still in the envelope, which tends to further reduce the condition as a serious factor, unless they're really severely thrashed, to the point where the buyer pool will be reduced dramatically.

Obviously it's not that hard to ballpark the stars who have changed hands, and sort of get to an estimated value for those pieces.

When you get to the pieces that have never changed hands, there's two approaches you can take:

1) Assume that they've never changed hands for a reason, because demand for these is almost certainly really thin on the commons, which means that it could be challenging to find a buyer at any price when you go to sell yourself. Although sometimes you get lucky with finding the one buyer who desperately needs just that common and is willing and able to pay handsomely for it, simply because he's not going to find it anywhere else. My experience is that this is unlikely, often because people who collect those players aren't used to paying top dollar, and there often aren't many of them, so they know that they can usually dictate their price.

2) Attempt to interpolate a value for the commons. Some people look at a % of the star card value, often based on a relative % from nearby baseline sets. Certainly this is one way to go, although I would honestly be worried about such an approach overvaluing the commons, simply because there will be even fewer collectors jonesing for the commons from such an obscure set, compared to the buyer population for the baseline set, particularly because these are from the early 50s, and the nearby baseline sets are all heavily collected (including the commons), whereas this set is not.

My guess is that these two approaches should give you a good range, although it might be a little wide, which is a nice starting point to think about value. Then it's just a question of finding a point where you and the seller can agree, which might be within the range, or might not.