In my experience it's not that bad, but you have to speak in their language. An agreed spec and deadline is a contract, and now they want to get more for the sa

In my experience it's not that bad, but you have to speak in their language. An agreed spec and deadline is a contract, and now they want to get more for the same price. I'm sure they wouldn't let a customer do that, so they understand that if they want to change the content of the contract, they have to negotiate. That of course require that you have a sensible manager/boss, that doesn't force it his way.