Mukesh Ambani's Antilia in Mumbai, valued at approximately $2 billion, is highlighted as one of the world's most expensive homes. The 27-story residence features advanced engineering, a private theater, and a unique snow room. The article also mentions other ultra-luxury properties, like Villa Leopolda on the French Riviera, emphasizing that high real estate prices are driven by scarce land, prime locations, and unique amenities, often making these homes function as self-contained resorts.