I paid about $160 for mine, new. That was the lowest price I could find. I think $115 for a used one is a good price. There isn't much that can go wrong with it.
definitely a good price, remoras are generally at least 160,and the remora pros are about 50 or 60 more, darn good skimmer, IMO
i would if possible look into the one with the mag drive instead of the rio(if possible, or change the pump)
i'd get it