Make your "featured picture" the one that stands out the most. From there, make sure you have pictures of important details that are listed. Let's say it has a supercharger that he is advertising as a reason to buy the car, make sure you have a good picture of the engine bay. PhotosGuy is spot on regarding reflections/lighting. At car meets and race tracks, sometimes you have to work with what you have, but when a buyer wants his/her car photographed, don't be afraid to ask them to reposition the car to not only fit it better with the background and setting, but also to utilize the light however you see fit. Need to light the dashboard? Make sure the sun is shining through the window that best accentuates the dash. Try not to get overly zealous on reflections. I have taken a few shots with a forest in the background right after I waxed my car thinking it would help accentuate the shininess, but in the end made the paint look cluttered because all of the foliage reflecting off the shiny paint. Use DOF to your advantage to add an artistic look, and ensure the exposure is dead on. What I find separates a boring "for sale" point and shoot style ad is:
The poor quality ad typically has:
1. Poor or uninteresting framing
2. Long DOF, not highlighting any specific area
3. Poor exposure/poor lighting
4. Boring background (driveways, etc)
Avoid this things and it'll stand out above the rest. Make sure you background suits the intention of the car. You don't want to picture a Toyota Camry in an off road setting, but rather an interesting urban backdrop. ALWAYS make sure the car is as clean as it can be. Another tip is position yourself to the level that is most interesting. Cars are not interesting when the photo is taken from a typical 5'6" to 6'0ft looking down. If you 're taking a picture if mostly the headlight, get down and shoot it level which accentuates this highlight. Low shots can work too, as can high shots. Make it more interesting than walking up and arbitrarily pressing the shutter button.
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