We stayed in Carla & Ezequiel's apartment over the Easter weekend and really enjoyed our time there.
The location is difficult to beat, right in the heart of Palermo with bars and restaurants everywhere. As mentioned in some other reviews however there is a nightclub next door which opens at about 2am and can be a bit noisy, so earplugs might be necessary if you are a light sleeper.
For getting around the city we found the nearest metro stop was Plaza Italia, about a 15 minute walk away.
The apartment has everything you might need, the kitchen is well equipped and there is working air conditioning in the bedrooms and lounge which was very welcome.
Overall we had a great stay and would very much recommend this apartment if you wish to experience Buenos Aires from right in the thick of it.