Infinite runner 3D and lighting

Hi,

I'm working on a mobile Infinite runner in 3D and I want nice and optimized lights and shadows in my game.

So I'm facing problems.

First solution i though of : Lightmap for the environment, and blob shadows for the cars (player and obstacle) Problem is there is a lot of thing passing over the car like, bridges and stuffs (should have shadows on the car....) AND the road is separate with the environment, so when i bake the road will have random shadows.

Here is a screen.

So i though why I don't use light probes? I didn't managed to get them work, with the dynamic generation of the environment. It's maybe a solution, but if it is, i'm to shitty to understand it, and I still need help x)

So the question is what in this specific situation is the best way to have dynamics shadows on the cars?.

I though I could have lightmap on environment and true dynamic shadows on car. But I think this will be too expensive for mobile game, am I wrong? (plus I don't know how to do this in a proper way, without breaking the lightmap).

Last point. A friend of mine told me I should use lightmap for environement and projectors for the shadows of the things over the car, and for the cars. Would this work for specific shadows form? If so how?

As you can see I do need help. So thanks for reading me and for your time.