Gilgo Beach murder suspect Rex Heuermann once worked as an architect for former president Donald Trump, a report said.

The Trump Organization hired Heuermann’s architectural firm, RH Architecture, for a plumbing job on the 17th floor of the Trump Building at 40 Wall Street, TheRealDeal reported, citing a 2018 filing with the New York City Department of Buildings.

The project at Art Deco-style building was estimated to cost about $200,000, the outlet said.

Steve Lafiosca, the Trump Organization’s vice president of property management, was listed in the owner’s information section of the filing. 

The Trump Organization did not immediately respond to The Post’s request for a comment on the project.

Heuermann, 59, was arrested near his Fifth Avenue office last week and charged with multiple counts of first and second degree murder in connection with the deaths of Melissa Barthelemy, 24, Amber Lynn Costello, 22, and Megan Waterman, 27.

Rex Heuermann did a plumbing job on the 17th floor of the Trump Building at 40 Wall Street, records show.
Getty Images

All three women’s remains were discovered in the marshes along Ocean Parkway near Gilgo State Park in December 2010.

He is also the prime suspect in the death of Maureen Brainard-Barnes, 25, who was the first of the so-called “Gilgo Four” to disappear.

The married father of two pleaded not guilty to all charges on Friday, and is currently on suicide watch at the Suffolk County Correctional Facility.

Rex Heuermann's booking photo.
Heuermann was arrested last week on a slew of murder charges.

Trump scored 40 Wall Street from Kinson Properties in 1995 for less than $8 million, the New York Times reported.

Donald Trump.
Donald Trump’s real estate company contracted Heuermann around 2018.

Over the years, however, the wannabe mogul repeatedly claimed to have snagged the property for as little as $1 million, while also stating that the address was now worth up to $1 billion, TheRealDeal said in 2012.

More recently, 40 Wall Street made headlines as part of New York prosecutors’ investigation into the Trump Organization.

In 2012, The Trump Building was cited as being worth $527 million to lenders, but only $16.7 to tax officials, the Washington Post reported.

The Trump Building.
The 40 Wall Street address has repeatedly come up in the investigation into the Trump Organization’s activities.

In February of this year, the building was placed on a lender watchlist due to its rising maintenance costs and vacancy rate, according to Bloomberg.