Monaco Mansion: World’s most outstanding bachelor pads and penthouses also do not stand a chance in face of Monaco masterpiece. Like a crown, this penthouse is placed on top of Monaco’s 49-story building. It includes 6 bedrooms, covers 33,000 sq ft area, has second balcony and water slide there that takes one in ocean overlooking infinity pool. Currently this Odean Tour penthouse is still being made. However, it is ready to take market by its wheel in 2014. According to plan, this penthouse would be asking for a whopping $250 million that will make it most costly property ever. Only billionaires would be able to relish this penthouse’s luxuries.