I remember having to spend several hundred on textbooks at the beginning of each semester when I was in college. There were piles of thick books that I never went back to once the relevant courses were over. They just stood there taking up space and gathering dust until sold, donated, or buried in the recycle bin. I wish I hadn't have to buy them in the first place. I would have saved a bunch had textbook rental service been around (Oops, that tells how old I am).
Let me show you the benefits of renting a textbook vs. buying it with a concrete example.
Marketing: An Introduction by Gary Armstrong and Philip Kotler sells for $66.31 with free shipping on Amazon. You can rent it for one semester (130 days) at $21.21 with free shipping both ways. The cost is even lower with a shorter rental period. You can also enjoy risk-free returns within the first 30 days of rental. This option would save you to the fullest extent if you end up dropping the course and therefore no longer needing the book. From my experience, renting the book could save you more time and money than reselling it, considering the wait before the book gets sold and the costs of printing labels and shipping (definitely more than what Amazon covers given the volume of this book).
If you're in college or have a college student in your family, I strongly encourage you to try out textbook rentals. That will not only help you cut down college expenses, but will also extend the useful life a book and eventually be better for our planet!
Disclosure: I was compensated for my time for writing this post. All views and opinions expressed are strictly my own.