YA novel published in 80’s or early 90’s and read early 90’s. A poor girl moves with her small family to rural farm house, hippy-ish parents party a lot. I remember the dad being drunk and then having company. She misses their family van, which I think they lived in before. Her name may be Topaz. The striking thing about the story is her sadness and nostalgia.
Lost Classics of Teen Lit: Name That Book! 