WASHINGTON — With sirens blaring, a fleet of limousines and security personnel raced down Pennsylvania Avenue twice in less than 24 hours to deliver Donald J. Trump to inauguration events.
But he was not heading to the White House. He was going to Trump International Hotel.
It was a telling destination for those visits Wednesday night and Thursday afternoon. Perhaps more than any other location in Mr. Trump’s real estate empire, this 263-room hotel epitomizes the convergence of Donald Trump the global businessman and Donald Trump the president-elect.
The Run-Up
The podcast that makes sense of the most delirious stretch of the 2016 campaign.Conflicts that for months have been theoretical are now about to become real — most immediately a possible challenge by the federal government. It owns the building that houses Mr. Trump’s hotel and has granted him a 60-year lease. From the moment he is sworn in as president at noon Friday, Mr. Trump may be in violation of that lease, given a provision that appears to prohibit federal elected officials from renting the Old Post Office building, the Pennsylvania Avenue landmark that houses the hotel, from the government.
Guests at the hotel include foreign diplomats and politicians who could be looking to curry favor with Mr. Trump — but even the act of paying their bills as they check out after the inauguration may open Mr. Trump to a challenge that he has violated the United States Constitution, which prohibits federal government officials from taking payments or gifts from foreign governments.
Members of Mr. Trump’s new cabinet are also staying there this week, as are dozens of big-ticket donors to his presidential election campaign and inauguration. The hotel will also be the site of a prayer breakfast on Friday before Mr. Trump is sworn in. All these bookings mean payments to the Trump Organization for the hotel rooms, meals and other accommodations.
Woody Johnson, the owner of the New York Jets, and Duke Buchan III, a Florida money manager, were there this week.
David A. Clarke Jr., the Milwaukee County sheriff, a Fox News regular and a Trump supporter, was camped in the bar sipping Stoli Cranberi vodka. Among the other guests were Hary Tanoesoedibjo, a billionaire businessman and politician from Indonesia who is Mr. Trump’s business partner in two hotel projects there, and former Mayor Rudolph W. Giuliani of New York.
The minimum nightly rate at the hotel will be $735. One suite during inauguration week was offered for $500,000, with various perks. On Thursday, the president-elect attended a lunch with Republican leaders of Congress, cabinet members and hundreds of others in the hotel’s enormous Presidential Ballroom, which features nine glass chandeliers and gold and white walls. “This is a gorgeous room,” Mr. Trump told the gathering. “A total genius must have built this place.”
Nearby, in the lobby bar, guests drank Champagne and ordered expensive cocktails off a drink menu that includes a $100 libation called the Benjamin, made of vodka, raw oysters and caviar. Guests wore red and white “Make America Great Again” hats.
“That building is symbolic of the minefield that President-elect Trump has decided to walk through,” said Representative Elijah E. Cummings, Democrat of Maryland, who is the ranking member on the House Oversight and Government Reform Committee, which is charged with investigating any potential wrongdoing by government officials. “We are going now from the hypothetical to reality — and I myself am not sure where it is going to lead.”
Sean Spicer, Mr. Trump’s press secretary, defended Mr. Trump’s continued close ties to the hotel. “That he’s going to his own hotel? I mean, I think that’s pretty smart,” Mr. Spicer said. “I think the idea that he’s going to his own hotel shouldn’t be a shocker. It’s a beautiful place. It’s a place that he’s very proud of.”
Mr. Spicer added: “It’s an absolutely stunning hotel. I encourage you all to go there if you haven’t been by.”
The story of Mr. Trump and the Old Post Office began in August 2013, when the General Services Administration awarded Mr. Trump the contract that would allow him to develop the landmark tower.
His children Ivanka, Eric and Donald Jr. each have a small stake in the company that holds the lease. Mr. Trump, who owns the vast majority of the company, is the only family member with a financial interest in the project, however, investing roughly $2.4 million of his own money, records show.
The Post Office project is valued at roughly $200 million, much of it financed by Deutsche Bank, a favorite lender of the Trump Organization. The bank agreed to lend up to $170 million. The deal requires a Trump company to pay the government $3 million a year in rent from the hotel’s opening date.
“This is a location like no other,” Mr. Trump said in an interview in 2013. “You have the Capitol, you have the White House and right in the middle you have the Old Post Office.”
Mr. Trump was keen to begin construction and in 2014 boasted that the hotel would open in time for the 2017 inaugural parade.
At the time, however, few could have foreseen it would be Mr. Trump’s inauguration Washington would be celebrating, and the headache that would create.
The lease between the General Services Administration and the Trump company includes a clause — “no member or delegate to Congress, or elected official of the government of the United States or the government of the District of Columbia, shall be admitted to any share or part of this lease, or to any benefit that may arise therefrom” — that federal contract experts say makes clear that Mr. Trump will be in violation of the deal as soon as he is sworn in.
“The basic integrity and credibility of the president of the United States of the federal procurement and contracting regime is at risk,” said Steven L. Schooner, a professor specializing in government procurement law at George Washington University. “We are about to have a legitimate scandal on our hands.”
Representative Cummings, the Maryland Democrat, said he expected the G.S.A. to declare the Trump Organization in breach of the contract. Renee Kelly, a spokeswoman for the agency, would not confirm that it intends to take such a move, saying only in a written statement that the “G.S.A. won’t have an update until Friday after the inauguration.”
That a company Mr. Trump controls is a prominent tenant of the federal government is just the beginning of it.
His administration will assume oversight of Wall Street regulation, which includes policing Deutsche Bank’s activities.
The Trump administration will also direct American foreign policy and will probably be in regular contact with the diplomats sent by other countries to the United States. For Washington hotels, those diplomats’ visits are big business, and Mr. Trump’s Washington hotel has been actively courting them in recent months.
Mickael Damelincourt, the hotel’s managing director, has held meetings and attended social events with ambassadors and other foreign dignitaries, all potential sources of business for the new hotel, given that visiting delegations frequently come to Washington.
Mr. Trump’s lawyers have said he would donate any profit derived from foreign government hotel guests to the United States Treasury. But Mr. Trump’s critics say that would not eliminate the risk he would be violating the emoluments clause of the Constitution, which some legal experts say prohibits federal employees from taking gifts or payments from foreign governments.
Erwin Chemerinsky, the dean of University of California, Irvine, School of Law, said, “There is no doubt he will be benefiting financially from foreign government officials who are patronizing the Trump Hotel in Washington and other facilities around the world.”
Employees at the hotel — the bellhops, bartenders, restaurant servers and housekeeping aides — are deciding if they will join the local hotel workers union, a process Mr. Trump recently agreed to allow without protest. Signature cards are being distributed to new employees at the hotel who will decide if they want to be organized.
Labor disputes have ended up before the National Labor Relations Board, including one at the Trump International Hotel in Las Vegas. Members of the board will be picked by Mr. Trump.
“We want to get workers at the hotel organized, into a union and then negotiate a contract,” said John Boardman, the president of the local, which represents about 7,000 hotel and casino workers in the Washington area.
Employees at the hotel who might have discrimination claims or claims related to overtime pay, worker safety or health could end up having them investigated by federal agencies overseen by people Mr. Trump appoints.
And if the Trump hotel seeks to fill job vacancies with foreign guest workers — as Mr. Trump did at Mar-a-Lago, the resort he owns in Florida — the Department of Labor and the Department of Homeland Security would need to approve different aspects of the issuance of visas.
“Him being an employer can only lead to complications,” said Lawrence Mishel, the president of the Economic Policy Institute, a liberal research organization that studies labor issues. “It is inherent in owning a business.”
Already, Mr. Trump is suing two celebrity chefs for breach of contract after they backed out of the hotel development. The chefs had a change of heart about doing business with the hotel in 2015, after Mr. Trump made incendiary comments about Mexican immigrants. Both lawsuits are continuing and in one case Mr. Trump has given a video deposition.
Even the marketing of the hotel is sure to draw scrutiny. Earlier this year Mr. Trump’s hotel offered a $500,000 “inauguration package” to its wealthy clients, which included the opportunity to stay in a 6,300-square-foot suite, according to Travel Market Report, a news report that caters to travel professionals. Doug Gollan, a contributing editor and the author of the article, said hotel management told him that it had been sold.
The hotel has certainly had a rush of business this week from the inauguration festivities. The lobby has turned into the social center for Mr. Trump’s supporters, who lounged at the dozens of tables set up in the lobby, washing down bottles of wine and offerings from the bar menu, including the $120 Trump tower seafood platter.
The crowd in the giant room — the courtyard of the Old Post Office building — included Tony Romo, the Dallas Cowboys quarterback, and Mevlut Cavusoglu, the Turkish foreign minister.
Gentry Beach, 41, a prominent fund-raiser and friend of the Trump family, roamed the floor, greeting friends as they arrived for the big celebration on Friday. “How are you?” Mr. Beach, a hedge fund manager from Dallas, said again and again, as he worked the room. “How are you?”
The hotel has seen a rush of activity this week. Outside, District of Columbia police, in addition to private security, are being dispatched to help provide security as the hotel has become an early target of protesters, including one man who set himself on fire this week. Inside, the lobby has turned into a social center.
The hotel was sold out and the restaurant was booked.
“We are very busy,” said Patricia Tang, the director of sales and marketing for the property. “That’s about all I can say.”
