The value of a Kelly Gruber signed pennant will vary depending on the condition of the pennant. Prices for his autographs start at $25.00.
The value of an autographed Greg McMichael baseball is $51.00. Additionally, his autographed trading cards have a value of about $20, and he was a pitcher for the Braves and the Mets.
The range for a single autographed baseball from Joe Mauer is $40-$100 dollars.
In the low 1,000s
Just about $55
About $1,000 to $3,000
On Amazon, Vin Scully autographed baseballs can go for as much as $295.80
Anywhere from $20 to $40.
$1800.00 in good condition
Close to $300
Because you are asking the value of a Signed "Broken bat" I'm going to take it that you have a "game used" bat, used and signed by Kelly Gruber. A broken store model bat to display a signature will have very little value. The bulk of the value will rely on The provenance or authenticity accompanying the "Game Used Bat. With out any letters of authenticity as a game used bat, with the proper bat markings as a pro bat it will only sell as such. A Kelly Gruber "broken" pro model bat. As only a pro model bat it will still have a low collectors value because it is broken. A Kelly Gruber Signed "Broken" Game used bat would probably sell for about $75. -$125.,and less without a COA for both the Game used bat and signature. Keep in mind that most "Game used" collectors would rather have the item unsigned, and autograph collectors are looking for a displayable signature
I would estimate $15.00 - $30.00
I bought one for 65 dollars