I don't think litecoin will cost 5000$ in 2018, I believe$ 1,000 in the second half of the year. Buy some now.
Yes, 5000 dollars is too high to assume this coming 2018. So, it's the right time to invest and hold litecoin since it's price is very cheap to buy. Surely, its value will slowly and slowly increase day by day. But I don't closed my door to meet that 5000 dollars soon. That's a very good news to those who hold litecoin for long term investment.