You will invest long (3 -
5 years) should choose coin with good foundation, good dev team. Coin under $ 1 you can consider: Sc, Xrp, Bts, Sys, Dgb, Xem, ... You can buy and keep them, not just buy 1; you need to buy many different coin.
Also, you can refer to the ongoing ICOs projects, it can help easy you x2, even x10 accounts, but it is important to understand them as they will be at high risk. You can refer to the signature project I am participating in: NARBONNE.