We are so glad we stayed here on the edge of the wonderful Gracia district. We were able to easily visit the other districts but were able to stay removed from the biggest crowds.
We walked down to the Gothic District a few times (35-40 mins) for some Sandeman tours (which were also great), and walled to Park Guell (uphill part of the way and probably 30 mins total). If you don't want to walk, the apartment was a quick 6-7 minute downhill walk to the Diagonal metro station. I recommend buying a T10 as the per-trip price is half and you can share it with multiple people.
The most unique gelato flavors are just up the street, there are many restaurants and unique shopping all around, and it is quiet at night.
The hosts were very accommodating and allowed us to drop off our luggage early while it was being cleaned. That was very helpful.
The hosts have put together a guidebook and there are tons of brochures and maps etc to peruse in the office space. They also left us a guide map, which was so nice to have!
One note: the single room is connected by a ceiling height window to the bathroom, so when the lights go on in the bathroom, it will light up the single room a bit...so don't put the lightest sleeper in that room :)
We were very happy to have plenty of toilet paper, soap, and shampoo (not the case in our previous air bnb in Spain). There was a Nespresso maker (you purchase the pods from them on an honor system) which was nice for our early riser.
The place was clean, comfortable, wonderfully located, and had great wifi. Will definitely recommend to others and stay again if we find ourselves back here.