$50 is a very low money to start in investing. I prefer to you to join in some signature campaign and you can earn a small amount of bitcoin or just go in the trading but in trading there is a high risk.
Sorry, but I beg to differ, I don't think there is any low amount in trading. One can even make 100X profits even with the amount like $1, $5 or $10. It's less about how much money the investor has and more about how he use his skills. I have seen that some people have ruined their thousands of dollars in scam coins and on the other hand some people made multifold profits on their investments.
I think that's true what he says, that $50 is not a big capital. if you use the money with amount of $50 and buy bitcoin of course you will get is just some MBtc only and if bitcoin price goes up twice as much as the profit you get will not be too big. maybe you can adjust it with to buy cheap coins but have potential to rise several fold