The model looks alright (I love the wheels!). I don't mean to sound harsh with this but everything else (lighting, textures and materials) looks very basic.
Textures:
> Car body. What is the pattern? Is it rust or dirt? It just doesn't look right because it's spread out so evenly without any concern of the car's shapes. It would look much better if there more dirt near the bottom of the car and in the crevices. Same with the rust, maybe some patches and spots instead of that weird cloudiness it has on currently.
> Brick wall. You've got a good base texture here but the way it just blends the pillars all in there looks bad. Maybe add some crumbling detail onto the outside corners and some subtle shadow or dirt into the inside corners to break it up a little. Also, the way those graffiti tags flow over the pillars makes them look even more blended into the wall instead of protruding outwards.
> Ground. Another pretty good base texture here too although it doesn't look like asphalt. It looks more like a mix of concrete with rough gravel on top yet it does have a painted yellow line. The problem with the yellow line is that it blends into the road too much instead of being paint on top of it all.
> Headlights. It just doesn't look good them being just white. Make the outer glass of out of a real photo of a headlight glass and make it glow a bit. Look at how it looks like in Gran Turismo or Forza, for example.
Materials:
> Chrome. This is the weakest part of all the materials in the scene. First, the base color might be too bright and because of that the chrome parts lose the shape definition in the more brighter lit areas.
>Ground. It seems it's way too reflective. It's reflecting the car and the cardboard boxes in front of it. It looks weird because the ground clearly doesn't look like it's wet.
