Donald Trump has suggested that he plans to live part time at his Fifth Avenue penthouse after he is sworn into office in January.

This is an expensive prospect for NYC. The NYPD estimates the cost of the extra police presence to secure the president-elect and his family at $479,000 a day, according to Mayor Bill de Blasio, who requested $35 million to protect Trump from Nov. 8 to Jan. 20.

While de Blasio has been asking Congress to reimburse the city in full for the hit New Yorkers have taken on Trump Tower protection so far, the federal government hasn’t complied. And once Trump takes office, why should Congress pay, either?

American taxpayers already provide a home for the president and his family, one well-protected by the Secret Service, among other government staff. Trump’s transition team has said incoming first lady, Melania Trump, and the couple’s son, Barron, will stay in NYC so he can finish the school year.

Remaining in their $100 million apartment is a lifestyle choice by the Trumps — one that should be paid for by them.

It’s difficult to guess the post-inauguration security cost, because it is unclear specifically how much time the Trumps will spend in NYC, but he might be at Trump Tower every weekend. That’s $968,000 for a 2-day weekend — a cost of more than $50 million a year to New York City.

NYC could use that money. For example, the city will spend $100 million over the next four years to bring physical education in public schools into compliance with state laws — about a third of schools don’t have full-time gym teachers and more than a fourth lack gyms. Over the next two years, the money the city would save by not paying for security at Trump’s three-story pied-à-terre could allow our schools to meet the state’s requirements in half that time, and more important, get our kids into gym class quicker, improving their mental and physical health.

Trump reminds many New Yorkers of the worst guy we’ve ever met in an airport bar: enthusiastically sharing his ill-informed opinions, making advances and refusing to take no for an answer.

The least he can do is pick up the tab.

Liza Featherstone lives and writes in Clinton Hill.