I started with 0.25 BTC in January 2017. Bitcoin price was $998. I paid $250 totally for my invest. (Now in USD i have 3800:) Later my brother and i invested 1 ETH on July 2017 and bought some alt coins too. I think you should at least invest couple of thousands dollars, like 3-4k todays. There are some promising altcoins, follow and invest them. I tell you my favorites.

EMC2 (Einsteinium)

MONA (MonaCoin)

ADA (Ada Coin)

XRP (Ripple)

Good luck to you..