At WyzAnt you're an independent contractor. You set your rate, but WyzAnt takes a big chunk of it (though the chunk lessens over time). The web site has an easy user interface.
Your reputation depends on the reviews of your clients.
I was a math tutor. I have a strong background in math and did not have problems handling atypical math classes/assignments, but my clients complained that other tutors were not prepared for such classes. A tutor said they 'knew' algebra for example, but struggled with a unique algebra honors course the client was taking. That algebra tutor had to have passed Wyzant's algebra test (which you can only take once by the way), but the test does not encompass all that algebra can be.
I loved my clients and the reason I left was to pursue a degree. I still think about my clients and hope they are becoming successful mathematicians!