I'd start with 20 and wouldn't go over 30...
Those bindings are probably all dry rotted and ready to snap the first time he straps em on.
An offer of 40-50 for the nicer setup would be ok
"When I do good, I feel good; when I do bad, I feel bad. Thatís my religion." - Abraham Lincoln
Moral of the story: If your going to rob people, wear a diaper.