Cost: $250 for installation
Time: N/A
Theory: The stock leather was fifteen years old, so it was definitely in need of replacement. I bought a custom kit that included all pieces needed for the seats and it also came with leather for the door panels.
Opinion: It's amazing how much of a difference new leather will make for not only the appearance of the interior, but for the feeling you get out of it. After getting the leather seats done, I felt a great deal more pride in the car, especially when leaving the t-tops off.