It cost me $300 and 32 hours of training to become an NRA Certified Pistol Instructor. I team teach four classes per year through the local Junior College and Sheriff's Department. We follow the NRA curriculum with 10 hours of class room and 200 rounds live fire. Students must qualify for accuracy as per NRA requirements.
In order to qualify for a concealed carry permit in our state, applicants must complete a course taught by "an NRA certified instructor." There are such instructors in our community who teach a 3 hour class with no live fire. Their students are eligible for a permit. I know this because I process permit applications as a volunteer at the Sheriff's Office.
There were 5 students in my instructor course. I'm the only one teaching on a regular basis.
I don't brag about being an instructor, but it is rewarding to have worked with several hundred students over the last five years. We often have individuals who have never fired a gun of any kind, and who leave the class excited about firearms use and ownership.