Buying School Books

Today I bought my school books. I drove to the University and got the isbn #s for the books and came home and order online. I have four classes and currently three of them have posted their books. The fourth class is and MIS class and I am guessing that it will have an online text which might cost about $30. But for now I can get the books for the other three classes. For one of the classes I bought the book at the school because it was a bundle with other books. But the last two classes I bought the books through amazon. Amazon is currently having a deal where if you buy at least $150 worth of books from them they will discount $15. However, I found it cheaper to buy the books from the used. Here is how it stacked up:

MBA 230 $112.06 --- $112.06 -bought it at school
MBA 260 --- --- --- -No book yet
MBA 270 $158.25--- $105.55 -saved $52.70
MBA 280 $102.75 ---$38.48 -saved $64.27
Total $373.06 ---$256.09 -saved $116.97 or 32%

Its still a lot but it saved money.