They do buy rare books. Like all secondhand stores, you will need to call them or check their website for their terms. Condition, title, author, and general desirability are everything when it comes to books.
They have many books, old, new, and limited print. I do not think there's many books they would turn down. I know as a fact that they have a couple books over $200, so I would assume yes.
They have quite the selection, so I would assume that they buy as well as sell.
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