This is a special place. The cottages are very comfortable and have a beautiful view of Eyjafyallajökull and the Westman Islands in the distance. If you email or call they will give you a tour of their stables where they train horses and help injured horses regain their strength (including exercise in a swimming pool!). We met and chatted briefly with one of the owners, who was lovely. As a bonus, each cottage is equipped with a free EV charging station—the only place we stayed on our entire trip that offered this amenity.
This is a vacation rental, not a full service hotel. There is no front desk or restaurant/bar, so I would come with supplies. (The town of Selfoss is about 30 minutes away, and there is a little hamlet nearby with some limited dining options, including a good food truck that serves fish and chips).