Used Book Values
Condition is subjective and can vary widely. See What's My Book Worth? from the Pennsylvania Department of Education for industry standards used when describing rare or used books.
When determining value for taxes, it is best to check at least 3 sites and take the average value.
Here is a listing of some helpful internet sources:
Antiquarian Booksellers' Association of America
Find books for sale, dealers in your subject or geographic area and local book fairs. “ABAA has the strictest and most sweeping Ethics Code in the book trade, and all ABAA members are bound by it..”
“Abebooks, the world’s largest online marketplace for books, lists over 80 million new, used, rare, and out-of-print books from more than 13,500 booksellers..”
Alibris offers millions of new, used, and hard-to-find books from their worldwide network of booksellers.
Used book site owned by Amazon.com
Over 40 million new, used, rare, and out of print books available for sale.
This is a co-op of independent book dealers.