But the seventh-floor condo at 817 Fifth Avenue is no mere apartment. It is a Steve Wynn experience.

“I will tell you,” said Roger Erickson, the casino magnate’s broker, “it is out-of-sight fantastic.” After a separate source told The Observer about Mr. Wynn’s upcoming $25 million listing, Mr. Erickson was willing to describe the 3,900-square-foot, onyx-floored apartment, which takes up an entire floor of its mid-1920s building.

The place opens up onto a private elevator vestibule, lined with what Mr. Erickson described as “very discreet leather.” That leads to a giant room, created from the apartment’s original living room and library, facing Central Park. The old formal dining room became an eat-in media center: “It has no table,” the broker said, “but what would you call those things that sit in front of a couch? A little lower than a table? You can eat there; you can watch TV.” Sticklers who prefer to keep those two separate can use the new dining room, carved out of what was once kitchen space, maids’ rooms and a servants’ dining room.

Three of four original bedrooms were combined to make Mr. Wynn’s corner master suite, with a dressing area and “one of those infinity tubs,” Mr. Erickson said, “where the water kind of pours over the edge.”

Back in late 2004, all was not well with the apartment. In a suit against the building and 10 John Does—the former owner, the current and former tenants of a neighboring apartment, plus five inspectors and construction workers—Mr. Wynn and his wife, Elaine, complained about a burst ceiling pipe that caused “total destruction of numerous items.”

“That’s why he redid the entire apartment. It’s literally new,” Mr. Erickson said. The suit, which biblically declares that far-reaching renovations were needed to bring the apartment back to “its pre-Flood condition,” was settled, according to a separate source.

Considering that Mr. Wynn’s eponymous Las Vegas resort is the kind of place where suites’ foyers have granite wet bars, does his renovated apartment look like a hotel? “No! It feels really elegant; beautiful; prewar,” Mr. Erickson, his broker, said. “Everything is in light yellows and beige.”

Mr. Wynn, whose divorce was announced in March, and who was ranked No. 468 on this year’s Forbes list of the world’s billionaires, bought the place for $7 million in 2001. So is his new price too high? “I think not,” said Mr. Erickson (who was also interviewed for this week’s Observer Sit-Down). “That includes all the furnishings, and he tells me the furnishings alone are worth $4 million.”

The condo’s art collection, including a Matisse, is not included in the sale.

Money issues aside, mega-condos have tended to sell to foreigners, and foreigners have tended to like very high floors. But Mr. Wynn’s place is only on the seventh floor. “I have a wonderful customer from Russia who was explaining to me what the Russian is looking for,” Mr. Erickson said. “They don’t want high floors; they’re not into Time Warner or the towers; lower floors connected to the earth, like fifth through 12th floors; buildings that are private, like prewar buildings,” he added. “And comfort.”

mabelson@observer.com