How much is a 1989 Marty barret card?

Answer 1

Marty Barrett signed baseball card

A Marty Barrett autographed Baseball card is worth about $5.-$10. Prices may vary based on condition, and the type of authenticity that accompanies the signature. Signatures that have not been authenticated could sell at half the market value or less.

Once a collectible baseball card is signed the value of the card dramatically goes down as a collectible. The card then becomes an Item to display the signature. The bulk of the value relies on the value of the signature of the player that signed the card, and how well the card displays the signature. This is why it is not a good idea to have an expensive card autographed.

Answer 2

Less than 10 cents.