Starting from the Back

I started modelling from the back of the room and thought of working my way around the main shape of the room like the 4 sides then make what we need to make in the middle.

This is the model of the back of the room which I made taking inconsideration to make it low poly so it doesn't disrupt the engine. To keep it low a poly scene I made the boxes a different objects within the scene, this made it easier to model and keeps good poly count and also makes a good result.