Booking and pre-departure contact was very easy, the owners are super-responsive. We arrived to Reykjavik mid-day and picked up the keys at the owners' home. They were extremely nice and welcoming. We were provided with all necessary information about the house, the area and activities - basically everything you need.
The house is wonderfully located in a lava field. It is part of group of scattered summer houses with absolute privacy - sheep are the only neighbours you will encounter. The house is very thoughtfully designed (by the owner). It was only the two of us staying there but there is enough room for up to six people with sufficient privacy. For example, the two bedrooms are each located at opposite ends of the house. The light interior is very high quality and has this nice Northern, reduced feel to it and shows no signs of wear. The house was very clean and in an immaculate condition when we arrived, with fresh sheets and an abundance of towels, which is handy in view of the sauna facilities. All the amenities work perfectly including the coffee maker, sauna and fireplace (there was a pile of wood which was sufficient for the first two days after arrival - you can restock in Borganes). There is a Hi Fi set with fine speakers to which you can connect your I-Phone/Computer but bring the necessary cable (USB or this red and white one). However, there's also a nice collection of records including Leonard Cohen which become our favourite CD during the stay. This is a very cozy place for spending a rainy day inside reading and chatting. The patio has wonderful views (you see the glaciers, volcano and the sea in the distance) and the layout shields you from the wind. The house is easily accessible with any small car and within a short drive of up to 2 hours you reach the Snaefellsjökul peninsula, Stykkisholmur and the Reykholt area. It might be advisable to opt for a 4 wheel drive if you want to take short cuts here and there, though.
We were very sad when leaving after a week we spent in the house and recommend this place with no reservations whatsoever.