And no pension or IRA income?  He must have a lot of investment income, so maybe he should consider this new product:

"While dividends have long been a defining feature of stock investing — a sign of corporate discipline and investor reward — Roundhill Investments plans to launch the S&P 500 No Dividend Target exchange-traded fund on July 10 with the ticker XDIV. Its ambition is simple but strategic: track the performance of the famous benchmark while dodging its payouts. The fund will sell holdings just before their dividend dates — steering income away from ETF shareholders and, in the process, away from their tax bills."  (From Bloomberg)

It would help lower his Medicare premiums, too.  Bottom line is that if he can't remember to pay his taxes, he's probably not in the best mental condition to manage his investments either.  

Or maybe much of his income is from mutual funds, with high CGDs in December, and doing the 2210 with actual income can reduce the penalty.  

I encourage clients to freeze their Social Security online accounts, because it's too easy to hack them.  I suppose paper filing of the W-4V is still allowed, if anyone is left at the local office to process it.  

This is what Google AI says about setting up automatic ES payments, so it's probably wrong:

1. Using the Electronic Federal Tax Payment System (EFTPS): 

• Establish an account with the IRS on the EFTPS website.
• Schedule automatic withdrawals for your quarterly estimated taxes, including the amounts and dates.
• EFTPS offers convenience by allowing scheduling payments up to a year in advance and providing access 24/7. You can also modify or cancel scheduled payments and view your payment history.