i think the boat looks ok, i reccomend taking a peak at this here
http://www.cs.rochester.edu/u/jag/adventures/hobie16check.htmlthings to look for... one other things to check is when you push down on the bow of one hull, it should remain very rigid and not twist or flex, another thing i found helpful was checking the boat value on nada.com
if possible, try and get him to take you out, rig it, and sail with him, it can tell a ton about the owner and boat
hobies are great boats, i bought mine just last summer
