An unmonetized (account holders accumulate credit(s) per textbook(s) already traded/donated) college textbook exchange hub. Kind of like a distributed library

An unmonetized (account holders accumulate credit(s) per textbook(s) already traded/donated) college textbook exchange hub. Kind of like a distributed library of users holding textbooks for a finite period of time until it is eventually re-queued for someone else to checkout. Payment for textbooks exchanged are abstracted as credits according to some scraped average.