You have to keep the business on your terms. You have to do it respectfully as to keep your reputation intact. If you just can her then there is the possibility she may tell 10 others what you did. It eventually catches up to you.
Now I am not saying just jump at every request. Its your business and you are the professional. You have to educate her on how you will perform her request and what it will cost. If she expects something else then you have to explain that is not possible. But you have to be tactful and if it comes to parting ways you have to do it carefully. I have actually recommended other LCO's to certain customers if I couldn't fulfill their expectations. You may want to line up someone to who you can pass her on to if you find that she may be hard to please in your current situation.
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