According to Michael Cohen, one of his frequent jobs was renegotiating bills on Trump's behalf.

"A law firm would send an invoice. He didn't believe that the invoice was fair, reasonable or justified, so he would give me the task of renegotiating a specific bill," Cohen said.

Cohen recounted his work repaying approximately 50 vendors related to Trump University at a discounted rate. All but two of the fifty vendors agreed to the discounted rate.

"They just went away," Cohen said of the two vendors.

"Did you pay then?" prosecutor Susan Hoffinger asked.

"No, ma'am," Cohen responded.

Cohen said Trump told him the outcome of the negotiation was "fantastic" and "great."

"How did that make you feel?" Hoffinger asked.

"Like I was on top of the world," Cohen responded.

Cohen told jurors that he began working for Trump after helping Trump with a series of legal favors.

"We ended up overtaking the board and resolving the issue which was to Mr. Trump's satisfaction," Cohen said about the first favor related to a board at a Trump property. "He liked the way that occurred and then continued to ask me if I would assist in other legal issues or matters he had."

"Did he pay you for that work?" prosecutor Susan Hoffinger said.

"No, ma'am," Cohen said

According to Cohen, Trump offered him a job after he presented Trump a $100,000 bill for legal costs related to the earlier favors.

"Would you want to come work for me?" Cohen recounted Trump saying. "I was honored, I was taken by surprise, and I agreed"

When asked about the $100,000 legal bill, Cohen said Trump "asked if I would like to get fired on the first day." The bill was never paid, according to Cohen, who immediately left his law firm to work for the Trump Organization as Trump's special counsel and a senior vice president.

When asked about the kind of work Cohen did for Trump, Cohen responded, "It was whatever concerned him -- whatever he wanted."

Cohen said he reported "just to Mr. Trump."

Michael Cohen briefly introduced himself to the jury, telling them how his father immigrated to California after surviving the Holocaust.

"Four children later, here I am," Cohen said about his parents.

Cohen told the jury that he went to law school at the urging of his family, though he did not want to practice law.

"I wanted to go to Wall Street," Cohen said.

He briefly explained how he acquired wealth with real estate investments and taxi medallions.

"I ended up going into business with a friend of mine who had grown up with me and we started purchasing buildings," Cohen said.

Cohen stood up in the witness box so he could identify Trump in the courtroom.

"He is wearing a blue and white tie," Cohen said while looking toward Trump.

"The people call Michael Cohen," prosecutor Susan Hoffinger said.

Michael Cohen entered the courtroom and took his seat in the witness box.

Donald Trump stared straight forward as Cohen walked into the courtroom. He did not appear to look toward Cohen.

Michael Cohen recounted listening to a 2016 phone call between then-National Enquirer publisher David Pecker and Trump regarding Karen McDougal's story.

"He had the call put through, and he had a speaker box on his desk. Instead of lifting up the phone, he used the speaker box so I was able to hear," Cohen recounted. "He asked him how things were going with the matter, and David said we have this under control and we will -- we will take care of this."

"David had stated that it was going to cost them $150,000 to control the story -- to which Mr. Trump replied, 'No problem. I will take care of it.'"

According to Cohen, National Enquirer parent AMI would make the original $150,000 payment, with the plan for Trump to later reimburse them.