You may be lucky and find something in Belgrano R, Nunez, Coghlan or Colegiales. You can also look at "Zona Norte" (Vicente Lopez, Florida, Martinez, Olivos, San Isidro), all of which is a further outside the city but has a decent train connection to Retiro in the centre.
Even further out there are endless gated communities (country clubs or barrios cerrados) where you will find bigger houses with garden and swimming pool, but be ready to commute.
