There’s always more rust than you think. Check the cowls by pouring water in them and seeing if it runs into the interior. You really don’t know anything about the engines he’s selling. When was the last time they’ve run? The underside looks decent. If you can find a nice running car for $15k more, I would absolutely go that route. Projects have a way of taking longer and being more expensive than you think. That’s why there are so many project cars for sale. The last owner thought they could handle it...... Good luck!