Keith Ferrazzi is the author of one my favorite business/personal development books, Never Eat Alone. On his blog, he has success tips and this latest tip is great one about valuing yourself, your brand.

Generosity and working for free when you’re first changing careers is one thing; undervaluing yourself is another. If you’re an entrepreneur and you keep offering services without charge in a well-meaning but misguided attempt to raise business, you are telling people that your time is worth zero. If you give away your expertise for too long, people will value you at the price they are paying. The same goes for employees who want and deserve raises. Bust your butt and show your boss that the market value of your work is higher than your current salary. Now you should continue to be generous by offering extraordinary value for the dollar. But you can be deeply generous and able to pay the rent.