WEALTHY Hongkong families will soon be buying homes for more than $100 million only to demolish them and build new ones in their place. A local businessman last week spent $79 million on a house in Deepwater Bay. He is now planning to tear it down and replace it with a French-style mansion on the 27,000 square feet plot of land. It is believed that the total cost could hit $150 million once the bulldozers have moved in and a new 12,000 sq ft home has been built, decorated and furnished. Local tycoons demanding outstanding homes are commonplace in such areas as Beverly Hills, California. Luxury property expert Mrs Jackie Langridge said there were a number of individual houses in the territory now valued at more than the magic $100 million figure. ''When they go on to the market there's a good chance they will be bought for the land and not the property itself,'' she said. ''The buyer will probably want to build a new home and is quite prepared to spend the money needed to do so.'' The Japanese Yaohan Group holds the record for the most expensive free-standing house bought in Hongkong. It purchased a residence at The Peak belonging to Hongkong Bank chairman Sir William Purves for $80 million when the property market was at its height three years ago. The firm has maintained the house in its original condition. But businessmen are now willing to pay high prices for the prime land and have no interest in the house that might stand on it. Pre-war government units sitting on some of the territory's best land are among those most sought after. Interior designer Mr Simon Jackson has helped a number of wealthy families create new places to live. He said: ''They want to maximise the plot ratio. ''On many of these sites the existing property is not as big as it could be. ''It is usually an old building that does not have the grandeur the client wants. ''We are not pulling down the heritage. This is prime real estate with very basic properties on top. ''These houses were not made for tycoons when they were built. ''They do not benefit the land value or the person who is going to live there.'' Mr Jackson said to demolish a property and build a new one would cost an average of about $2,000 per sq ft. ''Some people may think it is a waste of money,'' he added. ''But, the way real estate works in Hongkong, it is all relative. ''It is a good indicator of what is happening here.'' Luxury property firm Prestige Homes has joined forces with Mr Jackson's own interior design practice to make the most of the trend. Prestige - which is owned by real estate firm First Pacific Davies - sells the homes to its clients. Mr Jackson's company then negotiates with the new owners on what changes can be made to the site. He is working on three sites at the moment. Mr Jackson has designed interiors for the rich and famous, including the families of Mr Li Ka-shing and Mr Henry Cheng, the boss of New World Development Company. He is in a joint venture with architects Denton Corker Marshall Hongkong. The firm designs the house before Mr Jackson's firm looks after the interior. Mrs Langridge, head of Prestige, said the firm dealt with 90 per cent of free-standing houses valued at $16 million and upwards in Hongkong. She said: ''These older houses are normally ones which were built just before or after the war for senior civil servants or heads of companies ''They are just not big or grand enough for the tycoons who want to live there now. ''Many of our clients have seen fabulous houses in the UK and America and they want something at least as good here in Hongkong.''