Remember, the 'customer' is always right. [=never argue with a customer]
He is one tough/tricky 'customer'. [=he is a tough/tricky person]
The company has good/poor 'customer' service.
(..) The contract is in the name of a Miss Hester Mofet. So nobody's been in here since ? Not to my knowledge. Privacy is a great concern to my customers. Yes. I won't disturb anything, I promise. I'll be outta here before you know it. - May I help you? - Yes, actually. - It's stuck. (..)1991 The Silence of the Lambs