I'm in a group of classes where all the students take the same group, an "integrated core" if you will. For the same 5 books, my classmates who went to our scho

I'm in a group of classes where all the students take the same group, an "integrated core" if you will. For the same 5 books, my classmates who went to our school's bookstore spent $450 +- $100. On Amazon, I got older editions of the same books for $130...