What is copyright law for selling a product with a picture of anothe product

Hi, I am selling repair guides that show you how to repair electronic devices. I am going in competition with another company that also sells repair guides with labels over the picture of the device that is being repaired. What is the copyright law in using an image of, say, an iPhone that is disassembled? Can apple sue me for using the image of a disassembled iPhone in my product? Or can they only sue me if I use their logo in the image? Also, can I use a very small picture of an iPhone the corner showing what it "looks like" not disassembled? Its very hard to find info on copyright laws for using photos of devices that everyone has. I know you can't use pictures of artwork, literature, or even cars without some kind of permission. Does electronic devices count? Thanks for your response.