This is a question that deserves more research. Based on my experience, the turnover rate in the industry is high. Most certified independent trainers I know eventually went back to their “day jobs” after unsuccessful attempts at starting their own businesses. There are also the large chain gyms but the turnover tends to be high in those as well due to the high-pressure sales structure. Like any other industry, a lot depends on individual circumstances. If you already have your name out there in your community, your chances of success are greater. If you’re just starting out with no contacts, it’s going to be a lot more difficult.