I have started this out with 17 bucks to begin with, I know it wasn't ideal and it was different times but now I had received and spent over 30 bitcoins in my life time. Most of them were from working and not trading but I had the chance to make a lot via trading and a lot of airdrops plus good ICO investments and all that as well.

The point I am trying to make is that you can have zero and still start somewhere, put in your own effort if your money is not enough, if your money is 500 bucks then find something that you think will go up a lot and invest into that, divide your money and put it on multiple stuff you believe in and one will go up. If you divide 500 bucks into 5 projects and only one of them makes you x10 return while others go bankrupt you still have 1000 dollars instead of 500 even with just 1 out of 5 successful projects.