What is the largest trade I can open?

https://www.ftmtrade.com/

FTM Trade is not a licensed or regulated broker even though it states offers that look good to be true. 

FTM Trade claims to be located in the United Kingdom. As per United Kingdom law, almost all firms and individuals offering, promoting, or selling financial services or products in the UK shall be authorized by the United Kingdom Financial Conduct Authority (FCA). However, FCA reminds the public that FTM Trade is not authorized by it. 

Moreover, the Belgian Financial Services and Markets Authority (FSMA) identified that FTM Trade was a fraudulent online trading platform. You can check the full warning from here.

The truth is, FTM Trade is not overseen by any regulators. That means your personal data or your funds in this broker are unsafe and cannot be protected by any law. We would recommend traders stay away from unregulated brokers like FTM Trade and trade with licensed brokers.