On "Happening Now" today, Jenna Lee took a special look inside the Waldorf Astoria's $4,000-a-night presidential suite, where almost every U.S. president since 1931 has stayed. 

Lee spoke with Matt Zolbe, the Waldorf Astoria's director of sales and marketing, who said that the suite is actually empty 30 percent of the time, until the president comes in town.

President Hoover started the tradition of presidents staying at the hotel when it reopened in 1931 after being closed for two years because of the Wall Street crash, he said.

Almost every president that has stayed in the spacious suite has left a gift inside, another tradition that Hoover started. The only ones who haven't donated a gift yet are Presidents Bill Clinton, George W. Bush and Barack Obama. 

So, does the POTUS actually pay the 4 grand a night out of the taxpayers' pockets? Jenna asked.

Zolbe seemed to imply there is a discount. 

"Close relationships require a close scrutiny of the rate," he said.

Watch the video above from "Happening Now" to see the tour of the historic suite. In the clip below, see Jenna's tour of the tunnels that bring the president in and out of the hotel. 

Jenna Lee sits in the rocking chair that President John F. Kennedy donated.
President Dwight Eisenhower donated this desk to the suite.
President Richard Nixon donated these wall sconces to the suite.
The president sleeps in this bedroom while staying at the Waldorf Astoria.
Jenna tested the bed inside the presidential suite.
Jenna found the special subway tunnel used to transport the president to and from the Waldorf Astoria.