There are many prices that a Justin Upton signed Baseball could sell for a few I've found are: $85, $138, $106, $100.30, and $162
32.000
depends who signed it
1p
$35.00
500$
about £400 - £600
10 dollars
Most of the basketballs are going to be worth around $125 to $150 each. The exact price will depend upon the condition of the ball and who all signed the ball.
From 800 to 1000
1 MILLION dollars!
if signed by all players then 150 -200 dollars
Yes, in terms of whether it was used in play for example. A ball signed by a player that was an official MLB ball in a World series is definitely going to be worth more than any ordinary ball signed by the same player.