Now is not the time to buy Bitcoin. Although it looks cheap, Bitcoin is very dangerous now. Anything is possible. Perhaps the cryptocurrency market is about to disappear, but investors are still numb.
There is no exact in buying bitcoin because everytime you have chance to buy bitcoin. Bitcoin is a kind of investment which is too risky because of unstable price on market. We still facing down trend market so its hard to send in high price so we need to wait more time until we up trend market.
Its not risky if you are not looking for quick profit. Buy Bitcoin today and in 3 years period (sometimes from now until 2022. you have to sell at the right time of course) you will have at least 10x your funds.