In my scene lights are simulated with an Hdri and an VrayLight which is simulated the sun.
Here are my light settings.
The light type is Sphere.
Hdri setting:
I instanced the VrayHdri map into the enviroment rollout, as you can see.
Post Work
I don't want to talk too much about post work because everybody have an own style, and I don't want to affect anybody. First I put another sky with huge buildings behind the scene. I changed the contrast, hue and saturation. A few details were added after rendering too, for example the dirt on the window, fog at back areas and dust. I changed dramatically the colors, because I wanted to give an orange hue, which made it dusty.