Start at the actual dealer site to see if they have Hi res images of the vehicle. This was very helpful when I built the Aston Martin Vanquish 7 years ago In most cases thou, you'll have to do some post-processing in PhotoShop using the skew tool to get them straighten out from slight perspective into true orthogonal views. I'll tell you what I finally did on the Vanquish is that I eventually purchase one of the hi-quality metal vehicles to verify some things I could not in the images.
Regarding the processing in Photoshop, do I need to purchase the software to use it, or is there a free version available?
There are a few free tools out there. One of the more popular is GIMP.
There is also Paint.net
Adobe also offers Photoshop online, but I believe it is fairly limited. They also (or at least used to) offer a 30 day trial of the software.
That should be plenty to get you started.
Just Google your Query friend there is an world of Images.. For instance you can get some images of salvage cars here.
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