Since you sold the home in May, which is in the second quarter of the year, the lack of a 1st quarter payment shouldn't be a problem. When you prepare your 2019 income tax return and if TurboTax indicates you might owe an underpayment penalty, work through the "Underpayment Penalties" interview and "annualize" your income using the interview. That process will move 1/4th of the gain on the sale out of the 1st quarter and into the 2nd quarter where it belongs.
"How can I handle the estimated tax payments to my best advantage?"
It depends on what you mean by that. If your desire is to file a 2019 income tax return that doesn't require a large check being sent to the IRS then make estimated tax payments for the remaining 3 quarters that comes close to that $40K figure. On the other hand if you don't like making a large interest-free loan to the federal government then make payments that cover 100% or 110% of your 2018 tax liability, getting you into the "100%/110% of last year's tax liability" "save harbor" to avoid an underpayment penalty. You'll write a large check to the IRS when you send in your 2019 income tax return, but that check won't include underpayment penalties.
Tom Young
