Explain how the whole vehicle is used
Tell the shop which rows are occupied, where the vehicle is parked, and whether your priorities differ for front and rear seating. Large rear windows and existing privacy glass need to be considered as part of the full vehicle.
Ask for product-specific information
If comfort in sun is a priority, compare the specifications of the actual films offered. A dark appearance is not a substitute for performance information. Ask which film line and shade are proposed for each window, and how that plan addresses your preferences.
Keep expectations practical
Tint is one part of cabin comfort. It does not eliminate the need for normal vehicle cooling or other safe parking practices. Ask for installation timing, care instructions, and the written warranty for the selected film before the work is scheduled.