If you have $ 1,000 and want to invest in altcoins at the moment, you might consider investing in Ripple (XRP), Cardano (ADA), Stellar (XLM) and TRON (TRX). These are all cryptos in the top 10 of the market and cost less than $ 1, which is excellent for people with low budgets. If you want to invest long-term and secure, you should invest and hold Ethererum (ETH) and Bitcoin (BTC).
You definitely make no mistake investing in those coins but they are already high in terms of marketcap and have less room to grow than early stage projects or ICOs. So it all comes down to how much risk you are willing to take for much higher gains.