I think $150 is high to for a used unit. I bought a 2 yr old ice cap 660 ballast w/ 4 sets of endcaps and new harness from a board member here a few months back and paid $95 shipped. I thought that was fair. If you can talk him down, i wouldn't pay more than $75 if i were you. You can get a new ballast alone for $150, plus end caps and harness for an additional $60 or so, thats brand new with a 2 yr factory warentee.