Looks like a big project. I believe you have to remove everything on the deck to replace the carpet. Lots of labor. Probably can be cleaned up and be a nice craft. You should have the motor thoroughly inspected. Would definitely make a great fishing platform. Sad to see toys like this neglected.
It also looks like the thing is hung by 2 or 3 slings. I believe this is pretty widely accepted as being one of the least preferred methods of lifting a toon.
See if you can clean the carpet and the seats first. Pretty confident a little bleach and water in a spray bottle can clean that up. Just spray it let it sit and watch it disappear. Then rinse with clean water and wipe with a towel. Stubborn areas can be done again. Then if you can get it clean make him an offer. It can be done!
