A rendering of the future National Science Foundation headquarters, in the Carlyle area of Alexandria. (Courtesy USAA)

A deal to relocate the headquarters of the National Science Foundation to Alexandria has turned into a big payday for a local real estate family, but the family is keeping the details quiet.

Hubert N. Hoffman and his family bought a string of properties along Eisenhower Avenue in the Carlyle area of Alexandria in the 1950s.

Last year — with the help of $28 million in subsidies from the city — the family won a deal to relocate the NSF and its 2,100 headquarters employees, contractors and scientists to an office building the family planned there. 

Now the Hoffmans are selling the NSF project to a real estate titan, USAA Real Estate Co., a San Antonio-based manager of $12 billion in assets.

How much money the family will make on the deal isn’t yet clear; both a broker for the Hoffman family and USAA declined to disclose the sales price. The transaction has not yet appeared in public records.

The 15-year lease, negotiated by the General Services Administration, is worth an estimated $330 million and Hoffman won the deal with the help of an estimated $28 million tax abatement from the City of Alexandria. In creating the Eisenhower Avenue Science Redevelopment District, the city agreed to collect no taxes on the building for the first eight years after it is built and the city won’t fully tax it during the entire 15-year lease.

The Hoffmans are also likely to avoid having to pay a $6.6 million commission to the brokers who won the deal, after a recent court decision.

“We are thrilled that National Science Foundation is coming to Hoffman Town Center,” said family member Jay Hoffman, in a written statement released by his broker.

Shareholders and partners in the family’s real estate include the Hoffman Family Trust, Holly Nolting, Thomas Hoffman, Nancy Connor, Timothy Hoffman, Hoffman Development and Hoffman Buildings Management Co., according to court filings.

USAA announced the deal Wednesday morning and said that it had agreements with developer Lowe Enterprises and general contractor Balfour Beatty to build the NSF project.

The building will have 704,571 square feet of office space and 19,437 square feet of retail on a two-acre site beside the AMC Hoffman Center 22 movie theater, a short walk from the Eisenhower Avenue Metro station.

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