I have never traded futures but I am interested in learning. In trying to open an account I am getting confused by the warning disclosures about my liability for trading a futures contract - what the real (maximum) risks are. Let's say I have $4k in an account and I buy 1 e-mini S&P 500 at 1200. This contract has a value of $60k, but the usual margin requirement is $500. My first question is about the warning that stop loss orders may not be executed. Why not? How can this happen? My second question is: under what conditions can I be liable for MORE than the $4k that is in my account? Am I legally liable for the full $60k if the market somehow collapsed and my stop losses were not executed? What about insurance? Are policies available and does it ever make sense to buy them? Thanks in advance for suffering my foolishness.