Former Trump Organization controller Jeff McConney testified that the Trump Organization switched from cutting Michael Cohen's checks from the company trust account to cutting them from Donald Trump's personal account when Trump was the president and living and in Washington, D.C. -- something that presented a challenge.

That led to testimony that suggested checks were sent to the White House while Trump was the sitting president.

"What did that mean?" the prosecutor asked McConney.

"Somehow we would have to get a package down to the White House," McConney responded, having testified earlier that Trump was the only person who could sign checks from his personal account.

"DJT needs to sign check," McConney wrote in one email that was shown to the jury.

"The check was drawn out of President Trump's personal account," McConney said. "We had to get it down to the White House for the president to sign it."

Former Trump Organization controller Jeff McConney testified that Michael Cohen emailed an invoice to McConney for payment, which was displayed on screen for the jurors, marking the first time the jurors have seen one of the 34 records charged in this case.

"Just a reminder to get me the invoices you spoke to Allan about," McConney had emailed Cohen.

"[Cohen] typed an invoice into his response email," McConney testified.

The invoice Cohen sent was ultimately sent to and approved by then-CFO Allan Weisselberg, McConney testified.

In an email shown to the jury, Weisslberg clearly wrote: "ok to pay as per agreement with Don and Eric."

Eric Trump, in the front row of the gallery, nodded yes repeatedly as the email flashed on screen.

The jury was shown the paper trail of handwritten notes from both controller Jeff McConney McConney and CFO Allen Weisselberg memorializing the repayment to Michael Cohen for his handling of the Stormy Daniels payment.

First, the jury saw a paper statement from Essential Consultants LLC, the shell company Cohen created to pay Daniels. Weisselberg had marked up the account with handwritten notes to outline the repayment plan.

Jurors also saw McConney's notes on Trump-branded letterhead. They largely matched the repayment plan outlined by Weisselberg, with some additional reminders, such as " x2 for taxes" regarding the plan to double the repayment to compensate for the taxes Cohen would owed on the payment.

Last, jurors saw an email dated Feb. 6, 2017, from McConney to Cohen with the subject line "$$."

"Just a reminder to get me those invoices you spoke to Allen about," McConney wrote in the email.

"I sent Michael an email to send us the invoices -- at least the invoice for that month," McConney testified.

Former Trump Organization controller Jeff McConney's handwritten notes from a conversation with then-Trump Organization CFO Allen Weisselberg memorialize a monthly reimbursement schedule to Michael Cohen that prosecutors allege was ultimately falsified to keep voters in the dark about the hush payment to Stormy Daniels.

"We were going to wire the funds monthly from Mr. Trump's personal account," McConney said.

Cohen was to be paid $35,000 each month for twelve months. "That was just math," McConney said.

McConney calculated the monthly payment based the $130,000 wire to Keith Davidson, Daniels' attorney, plus $50,000 to the IT consulting company Red Finch.

Cohen doubled the $180,000 total.

"Michael recorded $360,000 for tax purposes," McConney said. There was an addition $60,000 to be paid as a bonus after "Michael was complaining his bonus wasn't large enough."

Former President Trump, on his way out of court, slammed the proceedings as "a disaster for the DA."

"This was a very big day, a very revealing day," Trump told reporters. "As you see, their case is totally falling apart."

"They have nothing on the books and records and even something that should bear very little relationship to the case," he said.

"It is just a disaster for the DA," said the former president.

-ABC News' Kelsey Walsh and Mike Pappano