I have to say, not bad to stay here.
It is a really tiny room what they offer but now you can have a non-smoking room and also cost-wise very reasonable because conveniently located in almost in front of Amanohashidate Station and breakfast (buffet) & Onsen (hot spring&sauna) you can eat and use at Amanohashidate Hotel which is a sister grand hotel a minute walk away from the Auberge Amanohashidate. The hot spring ,I highly recommend soak in the morning as well, so you can see the view of Amanohashidate from open air bath.
There is a shower located on the grand floor so you can take a shower quickly after you came back from the beach. Also they have FREE laundry use on the grand floor. Of course, they can keep your luggage before your check-in and after your check-out.