The customer is always right - even when wrong

The customer never knows what they want at the beginning, and come up with extra things during the contract. How do you handle this?

"Let's consider that for Phase 2...."

"Let's consider that for phase 2..." is a great approach. It allows you to keep to timescale, and establish a list of further things for a next stage.

This benefits both you and your customer. The customer will often find it so beneficial that they stick with you through several extra stages and end up spending much more with you than in the original contract....