Gabriela's place was a great apartment. Very near Casa Rosado and the Obelisk. Gabriela had arranged a pick-up from the airport, which was much appreciated, since I got in close to midnight. At the apartment, coffee and croissants were waiting for me. Excellent service!
The only downside to the apartment is the noise from the street. When you're a light sleeper, it may be bothersome. On the other hand, it may be very hard to find a place in this part of the city that is quieter.
Bonus points: the building has a nice nostalgic elevator, which comes in very helpful in order to not drag your bags up the stairs.