A multifamily investor looked like it was changing its stripes when it bought the 1001 Brickell Bay office tower in Miami for $157 million in South Florida's second biggest office sale of the year. But maybe not.

The transaction remained off the radar since closing three months ago with Aimco buying majority control of the owner of the building on Biscayne Bay. The purchase was reported in the company's earnings report, and state corporate records now list Aimco executives as heads of tower-owning company.

The Denver-based publicly traded real estate investment trust purchased the 32-story trophy building by buying 95% of the interest in the tower's owner, Brickell Bay Tower Ltd. Inc. The off-market deal, which closed July 2, breaks down to $456 per rentable square foot.

The transaction is notable for the deal size as well as Aimco's concentration in the multifamily market.

Aimco, short for Apartment Investment and Management Co., owns several South Florida apartment communities, including the 31-story Yacht Club at Brickell south of 1001 Brickell Bay.

Its investment in the adjacent Yacht Club building played a big part in the decision to buy the office tower, said Aimco's Matt Konrad.

"Our ownership of Yacht Club next door was an absolute critical factor," said Konrad, regional vice president of transactions in Bethesda, Maryland. "We can add a lot of value through the assemblage of two terrific sites. Waterfront sites in Miami, particularly in Brickell, are few and far between. There are very few developable sites on the water, so we can add value by assembling the two sites."

The combined property gives Aimco 4.25 waterfront acres in the booming Brickell Financial District. Aimco has the right to build a denser project under city zoning without City Commission review.

But the company has no concrete redevelopment plans. Any demolition would be a long way away, Konrad said.

Aimco in 2016 obtained approval from Miami's Urban Development and Review Board to build a 61-story tower next to the Yacht Club on the same 2.4-acre lot. It hasn't pursued the plan, but now has a much larger footprint to contemplate.

"No concrete plans," Konrad said. "There's additional density there based on the by-right zoning, and it's an option for us to do in the future."

The 344,454-square-foot office tower with an 800-spot paring garage was constructed in 1985 on 1.8 acres. It was designed by The Luckman Partnership Inc.

The site offers views of Biscayne Bay from offices, terraces and a ground-floor landscaped plaza. Amenities include a cafe with bayfront seating, 24-hour security desk and monitoring system, dry cleaning and car wash, according to the tower's website.

The floor plates from the ninth to 12th floors are 19,000 square feet and 11,000 square feet from the 14th to the 32nd floors.

The seller was affiliated with Miami Blue Real Estate LLC, a company founded by real estate broker Carla Meza, who signed state corporate filings for the owner before the sale.

The transaction trails the biggest office deal so far this year, the $159 million sale of the 2 MiamiCentral and 3 MiamiCentral towers at the Virgin MiamiCentral train station to San Francisco-based real estate investor Shorenstein Properties.

In Miami-Dade County, Aimco also owns the Flamingo apartment towers in Miami Beach and Bay Parc apartment tower in Miami's Edgewater neighborhood.

This isn't the first Aimco move outside the multifamily realm. Konrad noted the company bought a portfolio in Philadelphia last year that includes offices.

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