An enormous custom estate is now up for auction in southern New Jersey — and although it cost its creators some $27 million to build, the reserve price is just $10 million. 

Located a 30-minute drive from Philadelphia, straddling the border of two townships — Moorestown and Cinnaminson — the approximately 40,000-square-foot compound is currently accepting bids through Oct. 9, the Wall Street Journal first reported. 

The megamansion’s owners, the pharmacological entrepreneurs Calvin and Orsula Knowlton, decided to try the auction route after struggling to find a buyer through a traditional listing, the married couple told the Journal. 

“It’s extremely unique, but it’s extremely unique in particular for this neighborhood and this particular marketplace,” added Misha Haghani of the auction company Paramount Realty USA, which is handling the sale in collaboration with Kevin Steiger of Kurfiss Sotheby’s International Realty. “It’s a home for which there are almost no comps.”

The Knowltons paid $640,000 for the 7-acre property in 2017. They initially, and simply, planned to restore and expand the early 1800s era farmhouse on the lot. 

The farmhouse turned out to be moldy beyond repair, but demolition of it proved a bureaucratic nightmare involving both townships’ zoning and planning authorities. 

Finally, in 2018, construction started on what ended up being a colossal and still not entirely finished homebuilding endeavor (the Knowltons eventually decided to stop working on the behemoth, as its next owner may have different preferences), according to the Journal. 

As it stands, the four-story residence boasts amenities including a chapel, a home theater, a wine cellar, six fireplaces, a golf simulator and an English-style pub. There’s even what Calvin Knowlton called “the most giant reflecting pool I’ve ever seen,” a double-height foyer with dual curved staircases, a sprawling dining room, and a sauna-equipped gym that can be accessed by what the listing describes as “a unique tube elevator” in the primary suite’s bathroom.

The exterior was inspired by Philadelphia’s Second Empire-style city hall building. 

Although the Knowltons moved into the manor back in 2022, they’ve been spending the majority of their time at their home on North Florida’s Amelia Island, and are selling as they anticipate continuing to mostly be there, they told the Journal.