Yes, it'll depend on everything. Condition as well as what the book is. .
if you had a certificate of authenticity or proof of authenticity, I'm sure it would depend on the book, the edition number of the book, and the author.
It depends on the book of course, but very reasonable.
They probably don't pay anymore than they would pay for an unsigned copy of the book. Only way to find out is to give them a phone call or something.
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