Yea, Mosh, I'm not gonna store 100 sheets of Cor-X. That's a waste of space. I store 100 18" X 24"'s and that lasts me a year. So yea, I pay $10 a sheet for Cor-X 4' X 8', or like $.75 a sheet when I buy a box of 100, so just so you don't have to do the math, it's cheaper like I said...FOR ME...