Would stay at again!
Excellent communications with their friend for check in. Door automatically locks after you but turn the key a few extra times to engage the deadlock when home.
We did an early checkin for 50 euro extra in cash... Of note, for us, wasn't available until 11:30 (we got in by 9 am) -- pro tip: foundacion joan tapies is across the street and has a luggage storage while you are there (we got the Art Pass which came with a cute little art "passport" you get stamped but in retrospect, the barcelona card may have been a better deal over the week we were there since metro and multiple bus lines around the corner).
Location as you can tell from the tips above was perfect... Strongly recommend the first tour of morning at Casa Batlló since you are just around the corner anyways. Two 24 hr convenience stores within a block but walk one block further southeast and there's a better stocked store.
Quiet clean location (you can gently feel a rumble only when it's very quiet at night, which is what I think some people mean by hearing the subway. No street noise from this interior facing unit), shelves full of multilingual books, comfy couch, TV. Well-placed outlets in the rooms. Nicely stocked and clean kitchen in terms of pots/pans/plates/even baking pan, but you'll need to buy eberything including salt/pepper (they have shakers but empty) and oil if you want to cook (which you will rarely want to, coffee shop not even 100' away, all of Barcelona to readily walkable). If you're not used to the trash/recycle/compost bins, would look that up on day 1 so you know how to sort!
Combination washer/dryer was a bit of a struggle for someone like me not used to it but great to have as an option for a longer trip! They responded quickly with questions. Dishwasher worked well and was lovely to have.