For reflections on a complex object like a car you would need a cube map generated in realtime. As far as I can tell, this is not yet possible in BGE. It would, however, be fairly easy to use a reflection map on the windows and fake the reflection on the complex curves using a blurred reflection map. Or deform a planar videotexture by animating the UV map depending on camera orientation to deform the mirrored image (no idea how to do this, and it is not trivial, but I found something similar on the net).
Using videotexture is technically the same as using an image texture as far as materials are concerned… Add a normal map, alpha map, template, mix texture, etc.