It's almost two weeks since original post but...
Check the sails, the battens, and the batten pockets (they can crack) on the used Wave. Check the hulls for deep cuts or scratches. Check for cracks in the hull around the sockets where the crossbars go in. Check the fittings where the shrouds and forestay connect for looseness. Look at the rudder pintels for looseness. If you price a replacement sail (about $700, I think) or hull (more than a sail), $2700 price becomes only a $1K less than a new boat when you add in the replacement costs. The Wave is pretty tough, pretty durable, pretty tight, and unless there is obvious damage or looseness, you are probably ok. Personally, I like new because I got warranty and I got best parts working new and don't like rehab.