The training institutions are basically foreign teachers. For example, it seems that you need to increase the investment cost, because they also need the agency fee to earn profits.
Ironically, the result of doing this is often more valuable and effective than looking online or even contacting teachers directly: because they have a professional service team-strong support before training and follow-up counseling after training, which are beyond the reach of network companies and lecturer teams, but this is the most critical thing in the training process-training, not just feeling a lesson, and how to make students apply what they have learned is king.
Bless you!