Here is an example of the client asking for a lot without the budget to justify the amount of work involved. The pictures show a before and after drop-in to a board room shot. The image was sent back and forth until the final image, see below, was accepted. However the individual portrait I had been tasked to drop into the shot had been executed under completely different conditions, making the finish incredibly difficult to achieve.
From this experience I have learnt in the future I must scrutinize the material I am to work with, and manage the budget accordingly with the client.