That can be tricky if you're trying to make a deal with someone else. I find with most cards I have a general idea of what the range should be in terms of value. And it's not just NPDTS cards. Beckett is all over the map sometimes it's best not to rely to heavily on it. Problem is value is a perception. If you're trying to trade with someone else, they may not hold the same perception as you. I, for example, will probably over-value Habs cards, and under-value Leafs cards. I would over-value Subban cards, and under-value...wait...who even plays for the Leafs anymore?