If there is such a thing as a perfect airbnb, Xabi&Almu apartment might be it. Perfect location, convenient, terrific host (thanks Alex), well-equipped.
Key elements: elevator from floor 0; one of the top 5 showers in my years of travel (!); well-equipped kitchen; great location; great view.
Location: it is on a steep hill; however, after climbing the lower part, there are two escalators and a moving sidewalk that carry you right to the door of the building. Go down the hill and the supermarket is to the left, the river is straight ahead, a taxi stand is right there, and Casco Viejo is to the right. Go up the hill a short way and there is a breath-taking view of the city, and many, many stairs that take you down into the middle of Casco Viejo.
The apartment: The apartment is clean and modern. We spent a lot of time sitting in the little "coffee nook" by the windows overlooking the rooftops of Casco Viejo. Every day we found something new in the view, including the funicular going up and down the hill. This is a marvelous feature of the apartment. It is comfortable, we did some light cooking in the well-equipped kitchen.
A special shout-out to Alex who responded immediately to our questions, and brought some needed supplies the same day we asked.