Hi there, a good price for this ball since it is used is probably between $50 and $60 depending on condition of ball and weight/specs. Since yours if 15lbs I would sell it for $55 or $60 plus shipping. If you want an exact price contact psaunders300, he used to work for the owner of InSite and he knows more about InSite then I do. Although I am a fan of InSite and might be interested in purchasing this ball, I'll have to see how much money i'll have left at the end of this month. Hope this helps.
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CHRIS FARLEY:1964-1997
JOHN CANDY:1950-1994
JOHN BELUSHI:1949-1982
JIM MORRISON:1943-1971
"NO RESPECT, I GET NO RESPECT."-the great Rodney Dangerfield