Driftboats are a very effective way to fish a lot of the tailwaters here in East Tenn.
Keep in mind though that someone has to row it, and you can't row and fish at the same time, and all your friends will act like morons when it comes to rowing (in order to fish more and row less).
Is it worth the money? It depends on what he's asking and the condition of the boat. You don't by chance know what he's asking for the boat do you? If you decide not to buy it, I might know someone who is looking for a boat.