What jobs could my brother do who has schizoaffective disorder?

Schizoaffective. If your brother is being treated for his schizoaffective disorder and is compliant with this treatment, his symptoms should be under good control. With all these conditions met, he should be able to do most any job for which he's qualified.
Schizoaff. job. Once stabilized with ongoing tx, most likely he can work in trades he is interested in trying out.