Broker Olivia Hsu-Decker was about to close the sale of a $6 million mansion in California's Napa Valley last month when the deal suddenly stalled. The reason: fish fossils.
The buyer had agreed to buy the house along with all its contents, from the linens and lamps to the couches and silverware. Yet there was one item the seller insisted on keeping. It was a giant sculpture featuring several fish fossils that hung above the dining room table.
The buyer insisted that without the fossils there was no deal. It was only after Hsu-Decker pitched in $60,000 from her commission to the price that the deal closed.
"That fish fossil almost ruined the deal," she said.
Haggling over fossils and forks has become increasingly common at the top of the real estate market. As more foreign buyers rush into the market for high-end properties, many are demanding that the deals include everything they'll need to move in immediately after closing.
(Read more:Hamptons beach home sales hit record)
"These buyers don't have time and they don't want to spend months shopping for furniture and all the other things they need," Hsu-Decker said. "It's worth it to them to just buy everything."
And "everything" means everything. Sand Key Realty in Clearwater, Fla., just sold a mansion listed at $12.9 million. Along with the 15,000-square-foot house and Romanesque pool, the foreign buyer agreed to buy the artwork on the walls, the dining-room table, dishes, cooking utensils, towels, rugs and even a collection of Christmas nutcrackers.
The deal also included several dog crates, dishrags and mops. The buyer even bought the frames around all the family photos scattered around the house.
"Luckily they let us take the photos out," said Rafal Wazio, the broker on the deal.
(Read more:Warning sign: Overseas real estate purchases slow)
As first reported by the Tampa Bay Times, the deal also included the cars in the garage: a Mercedes convertible and a Bentley Arnage.
In Manhattan, Ryan Serhant of Nest Seekers handled a deal for a $7 million penthouse in which the sales contract included the kitchen sponges, toilet brush and two jars filled with M&Ms.
"In this recovering economy, buyers are looking for properties that they can move right into," Serhant said. "For the most part, they'd end up not spending as much money than if they started furnishing from scratch."
While M&M's may be easy to value, putting a price tag on furniture can be a problem. Sellers negotiate based on the price they paid, while buyers negotiate based on the much lower prices commonly fetched for used furniture.
"The one issue from turnkey properties is the price match over the furniture," he said.
And, of course, fish fossils.
—By CNBC's Robert Frank. Follow him on Twitter @robtfrank.
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