Putting together this sort of photo is a bit of a logistical nightmare. Getting together all the keys from the owners is step one then you have to painstakingly move each car into the correct position. You'd be surprised how many times we walked up to an aventador to move it to find we had the key for a different one. Once everything was positioned tho it was then just the long process of trying to light everything.
As you can see in the above photo there was a massive shadow created by spot light behind the van. This was ruining my base exposure so I took my softbox on a monopod and just held it up to cover the light. This allowed me to get an even background exposure.
Insert handy friend to run around where I said and light the cars.
Now you can see the sped up video of me bringing everything together in photoshop. It is critical that your camera does not move in this process as you then have to minutely align the layers rather than just stacking them on top (using the lighten blend mode) of each other.