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.
(..) again like last week. See this guy? You see this guy? This guy don't want you to have the money. Because he wants to come back there and squash your head. I have one customer sitting here. What I'm gonna do? Business is bad? You opened a store in an Irish neighborhood. These are dirty people. (..)2006 The Departed