I'm sorry. I don't understand why, if you have money to possibly invest in bitcoin, you couldn't put some of it in the stock market (I don't know that millennials have "missed" the entire stock market at this point)? Also risky, and high right now, but you're not planning to retire any time soon, are you? Put a bit of money in a good no-fee index fund and let it sit. Then do whatever you want with bitcoin. Good luck to you either way.