New Guy......HELP!! 2000 GP1200r power loss

i got a friend who has a 2000 gp1200r that he wants to sell me for $1200 with a trailer its only got 75 hrs on it. but he bought the ski with 60 hrs on it and rode it for a little in salt water and he was going back to the dock one day n it lost all power but it was still running. he hasnt rode it since then. he took it to his mechanic and he told him the ski needs a new motor. i dont no if it just needs a top end rebuild or a motor b/c you can do a top end for ALOT cheaper than putting a new motor in the ski. anyone ever had this happen or know anything about it?????

Thanks!

Taylor