NEW YORK (NYTimes) - To approach the President-elect's home these days, it helps to know a few of the secret passwords: Gucci and Tiffany are the most obvious.
If one of those is your answer when the police officer asks your destination, you are permitted to proceed down Fifth Avenue to Trump Tower, which has a Gucci store on the first floor, and a Tiffany & Co. jewellery store next door, about 600ft (180m) below where President-elect Donald Trump lives in a penthouse suite. Otherwise, the officers posted at the corner of the block direct passers-by to the opposite side of the street.
As the police and Secret Service build a security zone around Mr Trump, the authorities are establishing a pecking order among pedestrians. At the top are luxury shoppers, who are permitted to proceed down Fifth Avenue just as they were before. Protesters are directed across the street, on the far side of metal barricades. And New Yorkers simply trying to get from 57th Street to 56th Street are already learning to avoid the block.
Presidents have always had homes other than the White House, but they tend to be on quiet, tree-lined streets or on ranches in Texas. Mr Trump, on the other hand, lives in a tower in Midtown Manhattan whose front entrance boasts his surname at least 13 times in seven different fonts. Now that one of the city's most famous and ostentatious residents will be president, the Secret Service and city officials are trying to figure out how to provide security for a man who enjoys living in a glass tower at the centre of things.
Already, a sticking point has begun to emerge between the Secret Service and New York City: what to do about the block of Fifth Avenue in front of the tower. While the Secret Service has told city officials it prefers that the street be closed to vehicles while Mr Trump is inside, the city has decided so far to keep it open, according to a law enforcement official who has been briefed on the issue and spoke on condition of anonymity because it pertained to a presidential security matter.
The city has, however, closed part of the street south of the tower, East 56th Street, at least while Mr Trump is at home, reserving it for his motorcade.
Whether the city shuts Fifth Avenue to vehicle traffic is likely to be among the topics of discussion at a meeting on Thursday (Nov 17) between police commissioner James P. O'Neill and members of the Secret Service.
On Wednesday, Mayor Bill de Blasio, speaking to reporters after a meeting with Mr Trump, said that in the coming days "we'll be in a much better position to give you a sense of the balance that we will strike" between ease of movement and presidential security.
"Obviously the traffic in Midtown has to flow, and obviously the President-elect and his entire team have to be protected," Mr de Blasio said.
There is a political dimension, too, that is not likely to go unnoticed. Mr De Blasio, a Democrat who had described Mr Trump, a Republican, as an unqualified and dangerous candidate for the presidency, seemed willing to dwell on the Midtown traffic situation and the prospect that Mr Trump's victory would make it worse.
Standing in front of Trump Tower on Wednesday, he said that "the traffic situation is a very real problem".
Mr Trump, for his part, has previously described Mr de Blasio as "probably the worst" mayor in the city's history.
And Mr Trump, who received less than one-eighth as many votes as his rival Hillary Clinton, in Manhattan, may not want Midtown drivers wondering if he is the reason the traffic seems to have come to a standstill.
Mr De Blasio said he intended to hold a news conference on Friday to inform the public about traffic and security matters around Trump Tower.
How much time Mr Trump will spend in Washington and Manhattan is anybody's guess. But as a candidate, he often flew back to New York late at night, just to be at home. And he has indicated that as president he would like to be here when possible.
Already, however, the White House contains at least one reminder of Fifth Avenue. The famous Childe Hassam painting "Avenue in the Rain," which depicts a flag-draped Fifth Avenue, has long hung in the Oval Office.
A spokesman for the Secret Service declined to comment about any security concerns the agency had regarding Mr Trump's residence in Midtown. But the issues that the agency is examining are likely to be far more complex than street closures. Mr Trump lives at the top of his 664-ft tower, meaning he relies on an elevator to come and go, a probable point of concern.
Still, amid such considerations, life on that block of Fifth Avenue carried on this week much as it had before the election. In front of Trump Tower, a uniformed doorman holding a window wiper politely asked a squad of rifle-carrying counterterrorism police officers to move away from the entrance so that he could give the glass a quick clean.
At nearby corners, four men bearing sandwich boards were trying to attract attention to a nearby fur coat store. Throngs of tourists walked into the Abercrombie & Fitch store, seemingly uninterested in the dark glass building across the street, where the largest national story of the moment was unfolding.
Inside the Gucci store, sales clerks waited for customers. And at the corner of Fifth Avenue and East 56th Street, one police officer working at the checkpoint explained the protocol to another officer, who had just arrived.
"If they're shopping, Gucci or Tiffany's, and employees, let them through," the officer said. "But hanging out? No."