Prices vary from place to place, but they are all around 3000~ 10000. In fact, if you pay the money, you will go back to school, otherwise you will worry that you won't understand in class. It is better to start reading training early, which is mostly psychological. They are sure to have some problems. But if you analyze the exam questions over the years, you will understand that the scope is too large, just step on it a little.