expanding:
2. The 2019 desktop software has the best tools for calculating what you might owe...if you use that every year. You would just use ALL your 2019 values....then switch to it's What-If worksheet (in "Forms Mode" ) to adjust your various expected 2020 income values, and increase your investment income to see what you might owe without paying the estimate...then pay in ~ that amount. But you pay the estimates separately .... TTX has no way to actually arrange the payment for you.
3) Yes, you will have to separately enter your estimated payment into the 2020 software when it comes out .
And note, that the might be an initial underpayment penalty calculated, even if you do end up with a refund. It's not something to particularly worry about as long as you pay your estimate on time in the proper quarter, But if there is, you can use the annualized income form (form 2210AI ) in the 2020 software, to minimize it or eliminate it.
____________*Answers are correct to the best of my knowledge when posted, but should not be considered to be legal or official tax advice.*
