Achamore House on Gigha, off the coast of Argyll, is up for grabs for 25 per cent less than it was when first listed - after it was on the market for £1million in 2012.
The 17th century baronial mansion is situated in two acres of gardens and includes eight public rooms, 14 bedrooms and nine bathrooms.
The category B listed building also comes with a billiards room, a wood-panelled dining room, parquet floors, ornate cornices and ceiling work, and offers breathtaking views over
Achamore Gardens and the Sound of Gigha.
Achamore House is situated amidst the world famous Achamore Gardens which were the creation of the late Colonel Sir James Horlick, who bought the island in 1944.
However, the majority of the gardens aren't included in the sale.
Gigha is populated by around 160 people and in March 2002 the community banded together and acquired the island - which is now owned by the Isle of Gigha Heritage Trust.
The original building - dating from the early 1600s - was redeveloped and extended by architect John Honeyman for the Laird of Gigha, Captain WJ Scarlett, in the early 1880s.
After a devastating fire in 1896, in which only the interior of the billiards room survived, Honeyman's firm took on the renovation work.
Stylistic evidence suggests famous architect and artist Mackintosh, and one of his employees, may have worked on the mansion's interiors.
A design of Scotland's national flower, the thistle, features in the property's drawing room.
Selling agent Savills' brochure read: "The world famous Charles Rennie Mackintosh had joined Honeyman's practice in 1884, progressing from working as a draughtsman to becoming a senior assistant in 1901.
"There is strong evidence Mackintosh himself worked on Achamore House.
"He and a colleague in the firm, James McNair, are known to have travelled to Gigha to supervise work.
"Several features in the house support Mackintosh's involvement.
"Most notably, his signature design of the Scottish thistle with the whiplash neck appears in the drawing room."
A ground-floor plan of Achamore House dated 1903, which appears to be in Mackintosh's style, is now kept in the Hunterian Museum at the University of Glasgow.
The opulent house has had a varied number of owners and visitors over the years, from the rich to the royals.
Baronet James Horlick, co-founder of the famous hot bedtime drink company, once owned Achamore House and in 2007 the Queen visited the mansion when she landed on Gigha during her 80th birthday cruise.
It has been operated as a B&B in recent years.
Caroleanne Gallagher, a property agent at Savills, said: "The sale of Achamore House offers a wonderful opportunity to join an island community, without extreme isolation."