I've stayed in many airbnbs and this appears to be a professionally run apartment. As such, it's nice, it's clean and it is well located. If you need a place to rest and base yourself in the middle of Barcelona, this is a perfectly fine apartment.
Where it falls down is the personal touches. Check-in for us wasn't smooth; we were left waiting outside the apartment for nearly ten minutes. There was no welcome pack, which is okay for me but I know many Airbnb users like it if there is something to greet them (milk, coffee, biscuits, etc). There is a supermarket just two blocks away so getting supplies isn't troublesome.
Location
The apartment is in a good location, just a short walk from Las Ramblas. The bus from the airport drops you off a few minutes walk away also.
Apartment
Clean & tidy. There's a TV (no smart features, so bring a Chromecast or something if you like Netflix), dishwasher, and well-equipped kitchen.
Accessibility
Third-floor with lift access. The lift is very small but worked fine throughout our stay.