You can buy now. For bitcoin it is not a big price right now. But it will recover it's price very soon. If you buy in this time, hopefully you will be profitable. So don't late buy as possible for you. In every day buy little amount and gather it for big hitting.
This is a very good time for investors to select good coin to buy and hold in the last few months of 2018. The market is showing signs of recovery very well and many of the coins are priced. It stabilizes during this time. Remember to study carefully before investing because it directly affects your results.