It seems that such an authenticated piece could grab $600 - $2500.
Estimates are given here on the basis of the sales of similar items:
Official American League baseball autographed by Billy Martin
Sports Illustrated Magazine 6/25/75 autographed by Billy Martin
Official American League baseball autographed by New York Yankees
legends including Billy Martin, [and others...]
Billy Martin autographed hand signed signature cut matted with color photo
8x10 Color photo autographed by Billy Martin
[All were available on Grand Stand Sports "Billy Martin Merchandise",
So far so good, but also:
Official Arizona Diamondbacks Card autographed by Billy Martin
So, your first option is to sell it to a dealer, but, as a site warns:
"If you want to sell a Billy Martin autograph, eBay is still your best
bet. A dealer will only give you about 50% of an autograph's value.
Thanks to eBay's extremely active baseball auctions, it's easy for
anyone to auction off single autographs or entire autograph
collections for their market value.". (SOURCE: 2Baseball "Billy Martin
On eBay, an item titled "BILLY MARTIN AUTOGRAPH AND CARD" is being
auctioned on a minimum "Buy It Now" price of $49.95 (higher than the
price of an autographed card at Grand Stand Sports):
Billy Martin Autographed Baseball
However, there are also items beginning with $1 bid...
See all related auctions:
(ordered by price, highest price first).
2Baseball also proposes, in order to being able to evaluate the piece:
"if you collect autographs, you definitely need a guidebook. It's the
easiest way to avoid getting taken. Dan Zachofsky's Handbook for
Collecting Baseball Memorabilia is a good source for information on
baseball autographs and their selling prices. The Standard Catalog of
Sports Autographs is another popular value guide. " (SOURCE: ibid).
Finally, the Billy Martin site's FAQ also addresses the subject:
"I have memorabilia/autograph of Billy Martin; can you tell me how
much it is worth?
Our memorabilia experts are able to provide professional appraisals on
all sports and entertainment related items. There is a nominal fee for
this service, which will include a written appraisal. We also are
actively purchasing vintage sports memorabilia and can provide auction
services for those who wish to sell their "
(SOURCE: The Billy Martin Site, <http://www.cmgww.com/baseball/martin/faq.html>).
I hope this answered your question. I searched for ["billy martin"
autograph] for to research this answer. Please contact me if you need
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