Depending on your information source, you will get a different answer to the question of what can be classified as a luxury home. The greatest difference in definitions is between countries; however, there seems to be agreement regarding the upper end of homes.
Homes that are unquestionably luxurious, are worth tens of millions of dollars or more. They have incredible amenities, professional landscaping and property planning, and are generally massive in size with ten or more bedrooms. These homes are advertised nationally and internationally. Real estate agents for these properties have additional responsibilities involving trusts, attorneys, and anonymity issues.
No one seems to question that these homes, often owned by extremely wealthy and usually famous people, are luxurious. In fact, these homes should be called "super luxury" homes to differentiate them from other high end homes.
In an entirely different class, the other group of luxury homes, are advertised locally. Property in the US that is valued at over a million dollars is usually considered luxury real estate. Consumers in high socio-economic groups are the target for these properties.
This second group of homes may have features such as wet bars, designer kitchens, wine cellars, theatre seating, in-ground pools, security systems, professional landscaping, heated floors, and tennis courts. These homes are generally larger than average with good locations, amenities, property entries, and entertainment capabilities.
Luxury homes tend to have entertainment rooms with features such as built in seating and high end, up-to-date technology for the best movie watching experiences. Designer kitchens are also very trendy in high end homes with features such as custom paneling for appliances, extra under-the-counter refrigerators or beverage centers, and wine bars that fit among the kitchen pantry and other storage cabinets. Designer kitchens also include granite countertops, high end fixtures, customized storage drawers, and pullout pantries.
There's no question that this second group of homes are also desirable homes to live in. However, are they really in the same class as homes in Beverly Hills which are also called luxury homes?
In both groups of homes, location, amenities, property entry, entertainment capability, and landscaping are considered. Most luxury homes offer a combination of desirable natural elements such as ocean proximity, views, or climate, and professionally designed landscaping and architecture. But really, if a 1.2 million dollar, lakefront home with a dock and a swimming pool is a luxury home, then Mariah Carey's home must be a "super luxury" home.