If I buy secondhand miners with 200TH hash power included in the package, how I would calculate time of investment return?
Since you are already talking about the time of investment return, you will not be happy when you invest heavily in mining, and it begins to look like your investment is being sucked away by the very many unplanned challenges that you will definitely face. There is no assurance of investment returns, you may even encounter losses.
Looks like it is financially better option just to buy 1 Bitcoin and wait for next price increase.
This may be the better option for you.