Odeon Tower penthouse in Monaco could cost a quarter-BILLION dollars

Click the image to go to a slideshow of the Odeon Tower in Monaco.
Click the image to go to a slideshow of the Odeon Tower in Monaco.

Just when we think maybe, finally we've seen it all, an extravagant new residence comes along that floors us all over again.

This time we're talking about the Odeon Tower in Monaco, a 49-story double skyscraper under construction in the most expensive real estate market on the planet. (Click here or on the image at right to see a slideshow on Yahoo! Homes.)

The Odeon is expected to have 70 luxury apartments, two "sky duplexes" of about 13,000 square feet -- and crowning it all, a five-floor, 35,500-square-foot "sky penthouse" with its own private swimming pool, according to press materials provided to Yahoo! Homes. (Related on Yahoo! Homes: A New York penthouse with a slide connecting two floors.)

The project won't even be finished before next year, but speculation is already rife over how much the penthouse will cost. $250 million? $280 million? $329 million? $387 million? The numbers seem impossible, even unreal. Yet a London estate agency did tell CNBC that sales are averaging about $7,700 per square foot, so if the penthouse keeps pace, that would mean a sale of more than $273 million.

Whatever the estimate, the consensus is that the home has a very real shot at the title of world's most expensive penthouse, currently held by London's One Hyde Park, where a penthouse reportedly sold for $212 million.

Take a video tour of the Odeon Tower below:

Also on Yahoo! Homes:

America's most expensive home for sale
The era of the $100 million house
One tycoon is selling twin mega-mansions