I have found the easiest way to do these is to wake up each system if the screen is not on and then take a photo of it with the surrounding items your looking for. Then get your isle shots from each direction. Don't jump around. Just go straight down the line. The more busy they are, the easier it is to do. A Saturday afternoon beats a Monday morning as I have gone on a weekday and literally been the only person in that department and had the store manager walk up and try to assist me.
Don't hide the fact your taking the photo's. This will get them excited and on the defensive.
If the store offers a price match, you should tell them that you don't feel comfortable buying something that fragile and expensive on-line and plan to make the purchase there and that your interested in the extended warranty. Tell them you want to be able to take it back if something goes wrong and not have to mail it. Then tell them you want to go home and compare the on-line reviews and compare the models. If you sell your story well enough, they will give you a business card, warranty brochure and stand there and let you snap away!
I have had it go the other way and was getting my last couple of shots of a very poorly displayed store and the manager was power walking toward me and did not look happy. I had what I needed, so I just walked a little faster than he was and got out of there.
When at home, I then reviewed the photos and calculated the answers to the questions.
All you need while in the store is a good photo shoot and get out. If you stand there and walk around in circles checking for things and counting stuff, you will be there too long and get the wrong kind of attention.
The letter is a 100% get tossed out type letter. I'd not show the letter if it's the processor audit.