It is completely free to open a trading account. There are no additional cost or fees.
You pay the same usual commission when you are trading which is the same as all other brokerages.
So if you are trading without much support from your broker, no ideas, no training, worst still, some of our clients told us they have no idea who their broker even is, it is just some hotline number (Btw, we are talking about the real person handling your trading account, not the brokerage firm), then you'll want to come onboard asap.