is it rare to see really huge boosts over the prices listed in the reference books for a 65 CH UNC bill, such as a Silver Certificate ? I am seeing price increases of 300-800% if you go up by 2-3 grades from a PMG or PCGS 65 on some bills. Instead of $30-$50, I'm looking at $200 - $600. On the one hand....I understand it's all about supply & demand and that the population can take a huge drop as you go from 65 to 67 or even 68. You can go from hundreds to just single-digits sometimes. I get that. On the other hand....some of the bills are SO SPECIFIC (i.e., Wide 1 vs. Wide 2, 1957 vs. 1957A, Star or No-Star, etc.) that it's hard to believe people are collecting all of the different variations. So you would think except for the true expert with lots of $$$$ that most would find them interchangeable and thus increase the supply. I'm just shocked because my impression was that there are not as many paper money collectors as coin collectors....there's tons more variations and types of bill than with coins....and some of these price boosts above the Reference Guides are the kind of boosts you see for super-rare coins with hardly any supply at all (i.e., 1927-D Saints). Thoughts ?