Time for a New Job

Scene: A phone conversation between a client and me—an art director.
Me: Hi. I was wondering if you received the invoice I sent?
Client: Yes, I received it, but I am not going to pay you yet.
Me: Why not? Was something wrong?
Client: No, I don’t need to use your design yet, so I will pay you when I use it.
Me: Well, I still need to get paid now. If a plumber fixes your toilet, you don’t tell him you will pay him as soon as you need to go to the bathroom, do you?
Client: That’s disgusting! My bathroom habits are none of your business, and as soon as I use what you sent me, you will get paid!