Absolutely.
Being able to politely walk away from a negotiation not in your favour is a powerful psychological edge and will actually contribute to the bottom line. You should be mentally willing to fire any of your clients at any time,while in practice this should be a very rare event this will help you mentally "frame" yourself as a cool polite professional rather than as a doormat.In negotiations if your not willing to walk away you are at a massive psychological disadvantage.
Be polite and communicative,go the extra mile sometimes,deliver and socialise with your client,but always pursue your own interest.If you dont get what want be willing walk away.
