Textbook costs are one of the more avoidable expenses in education if you know which corners are safe to cut and which aren't.
Edition matters more than most other factors
Before comparing prices across new, used, rental, or digital formats, confirm the exact edition required for the specific course — page numbers, problem sets, and even chapter organization can differ between editions, and a cheaper older edition can leave you unable to follow along with assigned readings or homework problems that reference a different edition's numbering. Checking with the instructor or course syllabus for whether an older edition is usable is worth doing before assuming any edition works interchangeably.
Access codes are often the expensive part, not the book
Many textbooks now bundle a one-time-use digital access code for online homework platforms or supplementary materials, and this code is often a significant part of the total price — sometimes required for the course regardless of whether the physical book itself is purchased new, used, or not at all. A used physical textbook without a valid, unused access code can end up costing more in total once a new code is purchased separately, since used codes are typically already redeemed and non-transferable.
Renting vs. buying used vs. digital
Renting is usually the cheapest option for a book you won't need after the course ends, but requires returning it by a deadline and following any condition requirements to avoid additional fees. Buying used costs more than renting but allows keeping and reselling the book afterward, which can offset some of the cost if the book has resale value later. Digital/e-book versions are often cheaper than physical copies and available instantly, but some students find on-screen reading and annotation less effective for reference-heavy technical material — a matter of personal study preference more than a fixed factor.
Comparing prices across multiple sources pays off
Textbook prices can vary meaningfully between a campus bookstore, third-party online marketplaces, and rental-specific services for the exact same edition — checking prices across a few different sources before buying, rather than defaulting to whatever's most convenient (usually the campus bookstore), often reveals a real, worthwhile price difference for an identical book.
The one thing people forget
Wait until after the first class session to confirm the textbook is actually required and will genuinely be used, rather than buying everything on a syllabus preemptively. Some courses list textbooks that end up being optional or only lightly referenced, and buying immediately before confirming actual necessity is a common way students spend money on a book that turns out to be barely used.