As mentioned, contacting the directly is recommended. My experience with their buy program: Much of what they buy depends on the value of potential resale. If the testing study material is out of date or irrelevant, they may offer to recycle rather than purchase the material. The offered prices are based on genre, turn-over of genre, and supply. The offers will be only a fraction of the value they think they can sell the book. And those prices can vary from store to store.
Best thing to do is call them and they would be more than happy to help. My favorite location is off Greenville in North Dallas.
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