Whenever you want to start any investment you start with what you have and when you do that forget about what people will say and how much the next person started his investment with, the way your pocket is, is different from how the next person's pocket is so always remember that all fingers are not equal. To me age has never been a barrier to join those who are investing so is best to do your thing because I don't think is illegal to start up investment when your age below 18 and they never stated it anywhere that you must be 18 before you start investing as long as you know the in and out of what your getting into then is ok with me.