Those prices are not meant for you. They are meant for people who don't know any better.
Also, lots of those prices are meant to be negotiable. You're supposed to ask for more than what you think you'll get for it, so that people can negotiate with you. If you'd accept a deal at $100, why not ask for $150? For all you know, you could get someone who wants to buy it for $150, or someone could negotiate you down to $125. If you're negotiated down to that price, you're still getting $25 more than you would have if you originally listed $100.
That's what I always do when selling my textbooks to other people, at least. That said, I never sold anything on craigslist.
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Zachnorn - <D
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