This apartment is a gem.
We knew the area was not Palermo or Belgrano, but we wanted to be able to reach both Palermo and Montserrat areas by foot, and Recoletta/Once seemed like the best choice.
The apartment is lovely and the hosts are amazing. They cater for your every need and really strive to make your stay as smooth as possible. The apartment is large, the Internet works great, there are lots of books and everything one can possible need for a comfortable stay (kitchenware, bed clothing, towels, utensils, electrical appliances). It is clean and well organized.
There is a large supermarket 5 minutes away and a subway station nearby.
It is a great choice for families with children. It is pleasant to return to after walks in Buenos Aires.
I highly recommend it and the hosts: I wish all AirBnb hosts were as friendly and accomodating.
All the best!