Instead, you want -- particularly as a consultant -- to be the guy giving measurable, predictable, huge impacts either to costs or, ideally, to driving revenue. If you cannot quantify your worth to the company, it will be quantified for you, and the default guess is going to be -1.5 * $YOUR_SALARY. If you can quantify the value of your work for the company -- by being the guy who makes them money using his bag of magic tricks that management frankly does not understand and does not give a shit about -- your market value will be far, far higher, whether you choose to take it in terms of dollars, flexibility, working conditions, or what have you.