In a nutshell, this was a great place to stay! Very happy with my experience.
For a private room, you essentially have your own private area that can section off from the rest of the apartment (possibly shared with another AirBnB guest, but there was no one there during my stay). The bedroom and bathroom were perfectly clean, and the bed was comfortable.
Joe reached out to coordinate my arrival and provide maps, power adapters and local tips for getting around Barcelona. Everything with booking and arriving was a smooth process.
The location is ideal. 15-20 minute walk to La Rambla and the Gothic Quarter, 25 minute walk to the Sants train station, and within 5 minutes walk of multiple Metro and Rodalies train stops.
To address a couple points from reviews I read before booking, I did occasionally hear other people in the apartment complex, but I didn't find it to be distracting or annoying. If you live in a city, it was nothing out of the ordinary for city apartment/condo life.
If I'm back in Barcelona, I'll stay here again. Thanks to Joe for a great place to call home base.