I have an appliance repair business. I charge for labor and parts. I mark up my parts a flat percentage. How do I respond when a customer wants me to breakdown the cost of labor vs parts? Because I know what they are really trying to do is see if they can find the part cheaper on the internet.
You are assuming that is why people want a breakdown. It’s totally reasonable to want to know the cost of part versus labor for a job. You don’t need to break it down by part number so it’s easy for them to cross shop you. Just give list out the parts with a price by each item and then the labor costs.
Also explain that when they buy the wrong parts (which will happen 50% of the time) that you are charging for the call. Also explain that any warranty you provide is contingent on you supplying parts that you know and trust.