You also need to bring your own lighting to get it to look like the pro's do.
Studio's are great. Freakin awesome if you know what you're doing and have all the equipment. I'll gladly do a studio session with anyone's car. But it'll cost a lot of money to do.
Reflections play a key part. Even more so in a studio environment, because you don't want the lights showing up in the paint, but conversely you want the light to show off the lines of the car by reflecting. So things get a bit difficult. Lots of time is involved too.
Sure you can just rock up and start shooting with an onboard flash, but you'll get better results in an industrial park in the fading afternoon sunlight IMO.
This is what a studio setup looks like:
See those lights? $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$