Don't be afraid of losing jobs because you charge too much. When I first started on oDesk I charged $10 an hour, because I didn't want to put people off. Then I realized that kids in my neighbourhood make more walking dogs. Since then I've put my rates up considerably, and even though I still get nervous when talking money, I've never had a client say it's too much.

Charging more lets people know you're serious. Low paying customers typically ask for way more "can you just" tasks, like changing the font colour a dozen times or moving something "just a little to to right". You don't call your lawyer to change the typeface on your legal letters.