This is Dave Duhamel's Inspection Pit. Only thing I did was add a bulb inside the house (which is too bright at the moment). I used an isolated rail to trigger the flood lights when the axle of a car completes the ground. I installed the pit at the end of the Arrival/Departure track in my yard.
Dave creates incredible models and his prices are VERY reasonable! I don't think the pit is on Dave's web page yet.