The Cottage overall is not a bad place to stay. It's very clean and has a large bathroom and living space for two people, and has all the amenities to make your time here comfortable. I will mention however that we found the listing's photos misleading. You do not get harbour views from inside the accommodation. To see the views shown, you need to walk up the back of the property (which can get quite windy) or look from the place you park your car (which happens to be right in front of the main residence).
Even though it's a separate building to the main house, it is directly next to their carport and the main window for the cottage looks into this. The front portion of the building the cottage is in is private - so you are essentially tucked away in the back corner. Because of this, the Cottage is not nearly as bright and well lit as the photos show. Again, these are not the worst things in the world, but I feel that they should be known to anyone looking at staying here. If you just need a place to sleep/lock up your luggage, this could be a great place for you. If you're after somewhere with an open space to relax in private, there are probably better options available.