When Blake Thompson decided to change careers and go back to college, he expected it to be costly. But he did not expect the sticker shock he encounters each semester at the campus bookstore.

“I have one book for each class. I have four classes. The original total [for the books] was $583.95,” Thompson, a student at John Jay College of Criminal Justice, said.

Rather than pay full price, he was able to save about $100 by purchasing half of the books used, but even that, he says, was not cheap.

“One used book was still $125,” he said. “Like one book is one night of work for me. If I work one night, I just paid for one textbook.”

In addition to used, digital textbooks, when available, can be bought for even less, but the newest and often cheapest option is rentals available through websites like Chegg.com.

Barnes and Noble College Booksellers has also launched a rental program called Book Renter on select titles last year, which is now offered on roughly 25 campus bookstores across the country, including the Borough of Manhattan Community College.

The savings are significant.

“We rent right now for less than 50 percent off the new book price,” said Barnes and Noble College Booksellers Vice President of Books Jade Roth. “So if you have a new book that's $100, the rental price is less than $50.”

That same book used would have cost $75, and the digital version, probably around $65.

While rentals might be the cheapest upfront method, they might not turn out to be the least expensive option overall. If you buy a used book for $75 and sell it back to the bookstore at the end of the semester, you'll get back 50 percent, meaning you only paid about $37.50.

But since stores will only buyback books it knows are being used next semester, there's no guarantee when you buy it that you'll be able to sell it back, making rentals the most reliable form of saving.

The process is also simple. You pay the fee and you get the book for the duration of the semester.

But be aware; if you lose it, or damage it, you'll be charged full price. Beyond that, renters can treat it like a normal textbook.

“Textbooks are there to be used and to help in the learning process,” Roth said. “Sometimes you need to highlight, you need to make notes. All we say is that they can't be too extreme. Light highlighting, light writing in the margins is accepted.”

With the option proving immensely popular at pilot schools, Barnes and Noble expects to expand it to more campuses by the end of the year.