The Moule Avenue beachfront home of Gribbles Pathology founder Wallace Cameron and his wife, Joan, will be put on the market this week with an estimated price of $25 million.

If follows the listing of two other Brighton mansions in the past fortnight - the Salvo family's five-bedroom home in Glyndon Avenue and the landmark Max Beck-built residence Kinane on The Esplanade - which have price hopes of $20 million.

Moule Avenue last changed hands in 1998 for $5.1 million. If it hits the $25 million target it will vie for Melbourne's most expensive status along with the cliff-top Portsea Spanish mission-style mansion Ilyuka, which is believed to have sold last December for $27 million.

Only three other private homes in Melbourne have fetched more than $20 million.

Activity at the top end of the market has been subdued since the sale of Ilyuka.

Real Estate Institute of Victoria figures show that 30 out of 45 of Melbourne's most expensive suburbs recorded median house prices falls going into spring.

And home values in Australia's most expensive capital city suburbs were down 6.2 per cent over the first seven months of this year, according to the property analysts RP Data.

By comparison, middle-priced suburbs fell 2.3 per cent and the cheapest declined 2.1 per cent. Marshall White agent John Bongiorno, whose agency sold three $6 million-plus properties in Toorak and Armadale last weekend, said although there had been an ''adjustment'' at the top end, there was still good activity in the $1 million to $5 million range. ''You are always going to have families wanting to take advantage of this,'' he said. Kinane set a record when it last sold, in 2006, for $11.2 million.

Kay & Burton Brighton agent Ian Jackson said there was interest from one local and two overseas parties, although not from the Melbourne Victory soccer star Harry Kewell, who is moving to Melbourne.''I sent out feelers to the club, but no, I've not heard a word,'' he said.