Lighthouse caretaker went stir crazy 60 years ago and chopped up his colleague, whence it has been unmanned. Lighthouse excluded but 29 acres and six bed house included.
Guess if it all goes wrong, there must be a book and film rights in there, just pretend you have got possessed or haunted.
http://www.telegraph.co.uk/property/house-prices/idyllic-scottish-island-sale-just-325k-has-chilling-past/