Most obviously, she possesses three items while he has only two, but these possessions also differ in quality: "my long hair" and "my jeans" are both tangible, but "the cars, the clothes, and the scenes" is a mix of concrete and abstract nouns. Along with a larger amount, there's a greater variety in type here.
When I referenced the song again to confirm all of this, I realized that the melodies for the two lines also demonstrate these differences. The line "She had the cars, the clothes, and the scenes" repeats a sequential pitch only once ("clothes" and "and" are both sung to F notes), but "I had my long hair and my jeans" is sung almost entirety to a single pitch (all Eb notes, aside from "jeans," which is sung to an F).
