Who says you have to work 100% off the client's terms? One of the things I love about being a freelancer is being able to decide what clients and projects I want to work on (most of the time), because not every client and project is a good fit.
From my experience, most clients are flexible to the way you do business as long as you provide value and are professional. Most will actually appreciate a freelancer who has their own way of doing things and sets proper boundaries and expectations.
RE: Life As a Freelancer: The Myths And Realities.