The sale of One Court Square by SL Green Realty and JPMorgan to a group led by David Werner is set to close today. Earlier this year, the buyers agreed to shell out more money to extend the closing date, pushing the total price for the Long Island City tower to just north of $500 million.

The price works out to a hair more than $350 a foot for the 1.4-million-square foot building that is triple-net leased back to Citibank through 2020, but will need a new mortgage in 2015.

At 50 stories, the Skidmore Owings Merrill-designed 1990 building is the tallest on Long Island and in the city outside of Manhattan.

The tower was marketed by brokers Douglas Harmon and Adam Spies of Eastdil Secured, who have so far this year dominated the investment sales market.

Last week, the duo put 386 Park Ave. South into contract to Billy Macklowe for $112 million in a sale by Savanna. They also put a 49.9 percent stake in 1411 Broadway into contract to Ivanhoe Cambridge, a Canadian real estate company, to revalue it at $735 million. Blackstone is the seller, while West Coast-based Swig Co. remains as a partner.

All the parties either declined comment or did not return calls. Werner’s office said he was on vacation, but we know he was sitting at the closing. So there.

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Vornado Realty Trust is on a roll as the publicly traded real-estate investment trust led by Michael Fascitelli and Steven Roth finally spends some of its $1.5 billion in cash.

We’ve learned that Vornado is in contract to buy the entire 33,389 square feet of retail at 680 Madison Ave. in a direct deal from Gary Barnett’s Extell Development and partners Angelo, Gordon & Co. for $280 million, sources said.

The price equates to $8,235 a foot for retail space that is being reconstructed to provide higher store ceilings and bigger windows.

Sources said about 13,000 square feet has leases out. Asking rents for the spaces are $1,500 for the ground and $350 on the second floor.

Joel Isaacs of Isaacs and Co., who represents the retail space for Extell, did not return calls for comment.

In 2010, Barnett paid $164 million to the Helmsley estate for the 150-year lease on the entire building.

Barnett, along with Angelo, Gordon and Vornado, did not return calls for comment.

Last week, Vornado bought a retail swath at 666 Fifth for $707 million, or around $15,000 a foot for fully leased space from a group that includes Kushner Cos. and Crown Acquisitions.

In other Vornado news, we hear that it is stepping up to buy a long-term lease on the office building at 75 Rockefeller Plaza at West 51st Street. The 600,000-square-foot building is being sold by Harrod’s former owner, Mohamed Al Fayed, who wants to retain the ground.

Pricing on the former Time Warner headquarters — a soon-to-be-empty building that needs investment capital but boasts a great location — was not immediately available.

Rental payments would also be made over time. At a guesstimate of $800 a foot, the value would come to about $480 million. Stay tuned.

That asset is being marketed by Cushman & Wakefield. Neither a spokesman nor the brokers, led by Helen Hwang, returned calls and e-mails for comment.

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Sitt Asset Management has signed a contract to buy 113 Spring St. in SoHo for $32.5 million. The 18,550-square- foot building on one of the best blocks between Greene and Mercer streets was quietly marketed through Richard Baxter et al at Jones Lang LaSalle. Neither Baxter nor Ralph Sitt returned calls for comment.

Current retail tenant Frye Boot signed a 12,000-square- foot triplex during the market doldrums at a blended rent of $75 a foot.

The Sitts recently closed on 450 Broadway for $11 million and are also in contract to buy a three-store retail co-op at 208 Fifth Ave., which backs onto 1130 Broadway.

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A “monstrous” 40,000-square-foot corner retail space at 575 Broadway at Prince Street in SoHo may become available if Italian designer Prada is unwilling to pay a new, higher rent for its part of the space and leases for two other retailers run out.

The Korean retailer Who. A.U. has its 8,500-square-foot space plus storage available for sublease through January, when its lease runs out. Its broker, Alan Napack of Cushman & Wakefield, said it may be available “if someone is looking for a holiday pop-up store.”

Lure Fishbar’s lease on the Mercer Street side of the building may also be added to the other two to make the giant space.

“If they want to stay, we will be happy to have a full conversation with them,” said Haim Chera of Crown Retail Services. Chera is now collaborating with the building owners on re-renting plans.

Chera says Broadway retail rents will soon approach $1,000 a foot and that “$500 is really an old number” since John Varvatos renewed for $800 per foot at 122 Spring St. “It will command a premium in the marketplace,” Chera said.

Of course, with many retailers trying to do more with less, it doesn’t mean it will be easy as pie to rent or that retailers will get forced into paying more for desirable store leases even when they are making money by the truckloads. If the economy gets bleaker, we could see another standoff.