Superb located. In walking distance from Sagrada. Hop on off bus stop is nearby and using Barcelona card you can quickly visit most important sites. Building is from previous century, so you can expect strange from modern point of view apartment plan, aged doors, and ancient elevator. But it's part of experience. What's worse is bad electrical wiring and due to it, you should be careful in using equipment at the same time. We had lights problem in bathroom on second day (light was very dimmed, always not existing). Air conditioning is at edge if outside is 35.
Be prepared that kitchen equipment is suitable for quick meal preparation (usually breakfast and some half ready stuff) so if you want to do steak or love cooking, this is not the place. But it's fine, probably you want to explore local cuisine in restorans anyway.
Supermarket is just downstairs, but be aware, not working on weekends. Working one is not far away.
We had a very nice check in experience, our host waited us outside. She gave us advices and explained how everything work.
All in all, good place to stay with family. Recommended