How marketable are school psychologists in private practice?

I know I want to be a psychologist and I am trying to decide between clinical and school psychology. If I went clinical I would rather work as a lecturer than a professor because funding for research is very difficult to find. School psychology is appealing because it allows you to combine clinical/counseling psychology and work with kids. However the salaries are a bit low so I was wondering if a private practice could offset this. How would a school psychologist market private practice and is this popular or very rare for school psychologists?

How marketable are school psychologists in private practice?
I too want to be a School Psychologist! I know that they can go into private practices but I think it would be more difficult to get patients because you wont be a "School" Psychologist. School Psychologist get to work with the children while they are at school and get to see how they behave during classes, so if you are not actually at a school, then it may be more difficult.