hmmm, what happened to the front?
Looks like you wanted to align it with the bg, but it should be the other way round, align bg with car
Rims are a bit on the small side and the rear one is off. Also, don't add smudgy shadow on them
The body itself lacks reflections. My advise would be to rebrush smaller parts to begin with and work your way up to entire cars
Keep it up