A psychiatrist in private practice by far. There are some large difficulties with this option. First of all there are not a lot of psychiatrists in private practice. If some one with a psychotic disorder is very disruptive the psychiatrist will refuse to see the patient. The treatments provided will be limited which is a feature not a bug. Both too much treatment and too little treatment can have very negative consequences. The treatment that a psychiatrist in private practice gives should involve talk and medications where the patient basically talks about anything the patient wants to talk about that relates to how the patient is doing. A psychiatrist in private practice should be willing to talk to individuals which is not a given. Some psychiatrists see themselves as pharmacologists. A psychiatrist in private practice can call things by their true name. If someone is disabled due to a psychotic disorder the psychiatrist in private practie can state flatly to any funding authorities and to the social security administration that the patient is disabled due to a psychotic disorder. At mental health clinics there is lots of pressure to say individuals can work when this is not so. The mental health clinics will get paid either way as the patient is disabled and needs medical care.
A relative with a psychotic disorder who sees a psychiatrist in private practice will appear to be just running in place and not getting anywhere but the alternative is to fall off the treadmill at a mental health clinic with very serious consequences. Family would be very important as the ill relative is going to be quite isolated.