This unfinished Park Slope edifice may look like a treehouse that Howard Hughes built over fifteen sleepless nights, but by the end of this year it'll be transformed into a $25 million manse that has taken ten years to complete. "We love Brooklyn, but this has been a nightmare," the house's owner, Ivona Hertz told the Post. "We went through such heartache. This house has been blood, sweat and tears." They'd better wash off all those bodily fluids before they hop into their Olympic-sized lap pool.

The home has racked up 36 DOB complaints since 2004, and six violations (though they've all been dismissed). Last week, a stop work order was served for "FAILURE TO PROVIDE SIDEWALK SHED," though that order has also been rescinded. “I feel terrible for our neighbors. It is an eyesore,” Hertz said.

The eco-friendly mansion has a geothermal system, heated concrete floors, Brooklyn-made artisanal furniture and Brooklyn art throughout.

Over-the-top luxuries include a five-car elevator garage inside the house, an indoor Olympic-size lap pool, Jacuzzi and sauna, a gym, a regular elevator and three kitchens, including one on the roof, along with an outdoor rock-climbing wall. The home will have floor-to-ceiling windows throughout and about $1 million worth of glass for the all-glass front entrance.

“We wanted this house done when our kids were small,” said Hertz, who runs Ocean Empire Management with her husband, adding that her children are now off to college. “It’s too big for us now.” Yes, empty nest syndrome can be tough, even if you live in a geothermal ostrich nest with an elevator.

Our own Derek Evers has lived across the street from the monstrosity for eight years and says that Hertz's apology is cold comfort. "To call it an eyesore would be an understatement," Evers said, as he leaned back into a rocking chair and cast a piercing stare at the unfinished home. "Aside from the noise and blocking the street with large vehicles, they've been blocking three parking spots for ten years! How can the 4th Avenue re-zoning allow for a single-family home that big?"

Evers said that during the tornado in 2010, the buildings' scaffolding damaged cars and surrounding property, and added that the block felt eerie when construction stopped for several years. "We figured it was a casualty of the housing bubble," said Evers, who regularly uses terms like "housing bubble" and "recession" in casual conversation.

"I hear the DOB sometimes orders emergency hot tub inspections at odd hours of the night," Evers said. "And that they occasionally deputize neighbors to co-inspect them, too."