With or without a stake in WinRed, key aides have positioned themselves at the center of a formidable political machine. Ms. Walsh-Shields’s consulting firm receives a $25,000-a-month R.N.C. retainer and 1 to 5 percent of money it raises for the party’s 2020 convention. Mr. Shields’s firm, Convergence Media, represents clients ranging from the National Republican Congressional Committee to Representative Devin Nunes of California, one of the president’s staunchest defenders against impeachment.

But it is Mr. Parscale who has most often been the focus of Mr. Trump’s complaints that those around him are making too much money from his name and brand. Mr. Parscale has not always discouraged suspicions. A few weeks before the 2016 election, the campaign staff gathered at the Whiskey Trader, a watering hole near Trump Tower, to play beer pong and brace for near-certain defeat. In walked Mr. Parscale, returning from dinner with a new campaign hire.

“I’m making so much money!” Mr. Parscale declared, inserting an expletive, according to two people who were present.

Mr. Parscale, in a statement, called their account “untrue and ridiculous,” but since his appointment as campaign manager, he has bought a $2.4 million canalside home in Fort Lauderdale, Fla.; two condos, owned with his family, together worth $2 million; and a Ferrari. A campaign official attributed the spending to Mr. Parscale’s relocation and divestment from businesses in Texas.

But after a rival aide left an underlined copy of a Daily Mail story detailing his spending on the president’s desk, Mr. Trump summoned Mr. Parscale for a pointed lecture, according to a senior White House official.

Others in his circle have made purchases of their own. Mr. Lansing bought a $1.7 million home in Washington last year, while Ms. Walsh-Shields and Mr. Shields bought a $2 million beach house in the Florida panhandle. Asked about the house, Ms. Walsh-Shields referred a reporter to her mother, who said the down payment and mortgage payments had come mostly from her. Mr. Shields had also recently sold the house he owned before their marriage.

That Ms. Walsh-Shields has endured is noteworthy. While Vice President Mike Pence said, in a statement, that “we are grateful for her hard work, loyalty and professionalism,” Mr. Trump has privately referred to her as a ‘leaker,’ blaming her for unflattering media coverage during her brief tenure as White House deputy chief of staff in 2017. He has pressed Ronna McDaniel, the party chairwoman, about Ms. Walsh-Shields’s role in recent days. And during a meeting last summer, after prodding by his longtime security consultant, Keith Schiller, the president asked if Ms. McDaniel trusted her, according to people with knowledge of the exchanges. “I do,” Ms. McDaniel replied. “She works for me.”