Well Joe, there's your problem! You're in Retiro, not Recoleta

The boundary, per
http://mapa.buenosaires.gov.ar/ runs down Uruguay and Montevideo! I live nearby (regular visitor to 5 Esquinas area) on Cerrito near Libertador, so I'm in Retiro as well.
Noise drove us out of a short term rental (early) on Arenales y Ayacucho last spring (Sept). Now that you're here, you can check for colectivo routes, etc. That is definitely harder to do on-line. And the owners/agents always say "It's really quiet.", as we specifically asked for quiet with a young daughter and a light sleeping wife. The other thing to watch for, if possible, is 'major' motorcycle delivery routes. That was more the problem on Arenales, along with a very active nightlife (or at least traffic going to/from said nightlife).
The problem with renting too short a time when you first arrive is that you'll spend your first days/weeks looking for a place, and you still may not have a lot better information. Unless you are really sensitive to noise, etc., a week can go very fast.