As far as interior goes, I didn't use very many details but it was more than enough for the camera angle I was going to use for the scene (Fig.06).

Fig. 06
Lighting
Before starting to texture I had to establish the lightning of the scene. I applied some basic shaders to the model – car paint, chrome, glass and tire materials. I used a plugin called Smart IBL which you can find here:
http://www.hdrlabs.com/ to set up the basic lightning. The scene is lit only by a direct light with soft shadows and an HDRI (the HDRI also acts as a background)(Fig.07).

Fig. 07
From then on I experimented with the intensity and the distribution of the light, as well as the color of the car (Fig.08).

Fig. 08
Texturing
I didn't want to bother to unwrap the whole car so I applied simple UV mapping all over the model and then used blend materials and different polygroups to texture the vehicle. Everything is basically layers of textures and shaders so I won't go in depth and show you every material but I will go through one of the fender materials (Fig.09).

Fig. 09
This method is not very effective, though can be good if you want to have more control over the rendered out result (when rendering out passes), at least not if you use simple Blend materials (VrayBlendMtl renders fine when rendering in passes). Also many of you might find unwrapping the model a faster way but I like having control over the individual materials.