It depends on your area, and how eager you are to sell. Is the propane bottle included? Is it full or empty? And you have to find a buyer that appreciates the esoteric value, which is typically the older folks. In my area, with the propane, it would be a slow mover at more than about $125. It's a fairly narrow market in my area, and coal burners seem to be much better sellers here.
EDIT: Right now, within a 50 mile radius, there are two identical grills listed for $50. They have been available for several days now, just waiting for the right person to come along.