As you can see in the graph the 3rd halving event is expected to be about 1,000% of price at halving time about 16 months later.

Check current halving estimate at https://www.buybitcoinworldwide.com/bitcoin-clock/

The graph was done Feb-2019. I extended the green line to the expected peak rise in Nov. 2021. Actual price will be much lower then the projected $18,000. More like $9,000. So the $180,000 will be near $90,000.  

Buy just before or after the May date. That is the expected lowest price. Hold on to it till it looks like it has peaked. You might want to sell off some when up before it starts down. To be on the safe side. In case it falls faster than you can sell. That way you will have some profit in the event it crashed.