WILKEY
SO FAR CHANGE SUCKS!!!!!!
1500
You should do a compression check and be sure it run's and check out the pump. But don't be thinking you are gonna just buy a hull and then build a ski for less than what he is asking for that one. I am not saying just go and buy it either but it is all there and all the little component's really start adding up when starting with just a hull.
Don't take this the wrong way, but you've missed some pretty key things so far. I'd say scour through lots of pics on here before you make a decision. Generally speaking though check compression, run it, ride it...then decide if it needs more work than you are willing or ready to do (motivation or finance wise).