Don't buy now with your money and put it all into it to get rich.
Put a little each month, no matter the price. You would want that for your children and grandchildren.
DCA is the solution for not being able to get swindled when China bans bitcoins again.
No matter how long it takes, it will pay off. You won't lose your home or have to move back into your parents' house
What you describe is dollar cost averaging, and that is always a good way to invest.

However, Bitcoin is a speculative investment not ever going to be a saving account.
Savings accounts never crash 40% in a day.

So don't treat BTC like a savings account, because that will hurt you when you need to withdraw the most.