Well these motors are rebuildable and are pretty reliable afterwards, but if it is as bad as you are saying i would say that he is looking at a minimum of $2500-3000. for that price you could probably buy a new powerhead. This is a carb engine i assume. If so I have a friend who has 2 1994 175's 25" shafts 1 running, 1 running but knocking, and a 1993 175 fast strike running but needs lower unit. He is looking for $3000 for all 3 of them. If he is interested email me at zachsvmax@comcast.net and i will get intouch wiht my friend. The only problem is that they must be picked up in south west florida.