You really have to look at the nature of your "edge" or setup and slice up how you get to that 5-10% number. To successfully earn a living on a single setup, I would imagine it would need to occur rather frequently, with each profitable trade making up a small portion of your monthly total gains (I'm lacking the proper vocabulary for each of these terms, I'm sure someone will step up). You can't rely on your numbers if you achieve them with only a handful of setups each month. That being said, if you've done all (I mean ALL) your homework, and if you are trading futures with an edge that is applicable on a daily basis, you really don't need that much money to earn a steady living.
The amount really comes down to how, for lack of a better word, good your edge really is. Can it earn you a decent living if you're trading a single contract? If not, how many contracts would it take? Multiply this number by the minimum overnight initial margin required for your market, then triple it -- I'd say that's a rough estimate for a minimum.
The amount really comes down to how, for lack of a better word, good your edge really is. Can it earn you a decent living if you're trading a single contract? If not, how many contracts would it take? Multiply this number by the minimum overnight initial margin required for your market, then triple it -- I'd say that's a rough estimate for a minimum.