Always set your reserve at the amount you are prepared to accept for the bass,that figure is up to you.Whatever you do is don't sell it for a ridculously silly amount because you quite often find that there is a buyer out there for your bass.Patience is the key.
It once took me 6 months to find the right buyer for my SC deluxe,i kept getting stupid offers,then someone happened upon it and it was exactly what they were after,some days i thought it would never sell,but everyone was happy!