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This is certainly a desirable set of books. The only problem is that these books are not in top condition. I can see general foxing (browning) and wear and nicks to the bindings.
In the condition pictured, the current retail (replacement or insurance) value of this set is approximately $6,000. If you were to sell it, you could expect to get the fair market (private sale or auction) value of approximately 40% of the retail amount, or $2,400, depending on location and actual condition.
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