The IB FFA is also very handy for simultaneously trading your own multiple accounts. e.g. cash, IRA, Roth. As long as you're not shorting stock or taking naked short call positions you can pretty much do anything you want in all 3 at the same time.
never trade for the member of the family, never give them investing advice... stay away from them u can screw general public (and that's what trading opm is all about), but do not touch your own family... if your granddad loves you so much he can just give you money (gift) for trading,.. if you will be successful you take care of him, if not (and that is a much higher probability) - well.. it was a gift anyway...
Dad/Grandad are just giving you the opportunity to get it out of your system before you 'get a real job',so you can't say 'if only I was properly capitalised' if only this,if only that.
Years ago last time I looked into this there was some geographical restrictions too, the investors had to reside in your state or something like it. Maybe it was just for non-relatives, I don't remember...
The best thing you can do is make a documents that says: this money is at risk and can be lost totally when loses reach 30% of het invested capital, trading will be halted and situation will be discussed, resulting in stopping completely or defining the new level of losses that will be accepted. Simple and very clear.
I would add a third statement to those ones: 3) I am in no way shape or form a professional or qualified financial professional, and have no certifications or experience of any kind investing for other people. I have no idea why anybody would trust me to invest their money for them, but if they are crazy enough to allow me to manage money for them, ALL risk is entirely theirs. I accept no responsibility what so ever for what is very likely going to happen to this money, which is to say, it will be lost. If he signs that, then good luck in your trading my friend