Wowzer; this place is HUGE (especially as there were just three of us rattling around in it) and it’s in a great location to boot.   This review is for a winter stay.   Pre-stay communication; perfect.
Getting to the house; easy. We took a cab, but the bus would have been simple too (which we took for our return to the airport at just over €5 P/P).
It’s on a tiny private street which has a guard/gate-man (with a lovely grey cat) during daylight hours, you have to lock/unlock the gate when he’s not there. Cabs will drop you at the end of the street as they can’t enter.
Check in; great (although lots of details to take in, so listen up!).
The house itself is massive, classically decorated with plenty of comfy sofas on which to stretch out. Felt like a rich friend’s house!  Lovely and warm.  The home entertainment system is brilliant (once you’ve worked out which of the 6 remote controls does what!) and we spent a great night in ‘at the movies’ with friends.   Each of the bedrooms is as nice as the others; spacious, comfortable and well-appointed. There’s a big jacuzzi in the room we took, which is a bit of a white elephant (a normal shower would have been better and easier to access). Really comfortable beds with nice linen.
The kitchen is well-equipped and set up for you to cook up a storm, assuming you fancy a night in. One (big) fridge for guests, the other for Joy (see below).  Joy cooked hearty breakfasts for us, but was pretty much invisible the rest of the time. She’s not very chatty (or perhaps it was just us!) and keeps out of your way. That said, you know she’s in the house so no wandering around in your pants!  The location is hard to beat with everything on your doorstep. We didn’t take the metro once as everything was walkable, including some ace restos (try Eldiset, 25 min walk, but so worth it).  The hosts were quick to address any problems and/or answer questions via the Airbnb app or WhatsApp.  In conclusion, this is a very special property and made us feel like we were staying in a ‘real’ Barcelona home. We’d love to go back, maybe in the summer.