Which color questions matter first?

I have booked my first proper color appointment, and I am trying to arrive with a useful description instead of a heavily edited photo. The hair I have now is a fairly ordinary brown and my skin is fair, so I am considering a cooler change rather than a bright copper or golden blonde. Most of the examples I saved were photographed in very flattering light. I cannot tell which of those shades would still look balanced when I am outside or under office lighting. I would like to compare two nearby shades. Regular root maintenance would be difficult for me to schedule. I am using cool summer hair color ideas as vocabulary for the consultation, not as a strict rule about what I should choose. Would it help to compare sample swatches against my face? I can take pictures in natural light, but I am unsure how much to trust a phone camera's color balance. The cut itself will remove several inches, so I would rather make the color decision thoughtfully than change everything at once. A small test seems easier to evaluate than a dramatic leap. For anyone who has tried a subtle cool shade, what made the consultation more useful? I am especially interested in how you weighed everyday lighting, upkeep and the condition of your own hair.