There are lots of programs out there that search for edges or differing light conditions, but I have yet to see one that did a batch-job well. Knowing that batch isn't a consistently reliable method I have to assume your person is manually inspecting each image. I wouldn't call that a very scalable business, but that's his problem.
<Disclaimer on next statement>I must admit that I have a trained eye. I am an avid photographer and have years of experience with Photoshop from a photography and graphic design standpoint, so I might be seeing more here than the average person </end Disclaimer> This image looks insanely fake to me. The reflections on the body and in the window lack context so they immediately hurt my eyes when looking at this. The driver's side windows are the ones that really stick out. It just isn't natural.
I must admit there are some pieces that are truly outstanding:
1. The pavement cutoff
2. The smooth edges where the background was cut out on the vehicle
Those are tough things to do and take some time. If he was able to mask the reflective parts of the windows and duplicate the body areas to stop the reflections there, you'd have something very special.
I'm not suggesting that using photoshop is the way to go. My friend is at an urban dealership were space is at a premium. Most of his vehicles are parked on a gravel lot. He is aware that his pictures are not going to look as good as those shot in a booth. He is simply trying to make them presentable. He wants people to focus on the vehicle and not the surroundings and I think that he accomplished that. As far as scalable, these pictures are taken by an employee. He maintains a days to market of under three. Being a person of integrity, he is not going to remove dents, dings or whatever. This is an example of someone being creative in making something work with limited resources.