Richard y Lety are great hosts, very welcoming, and have a beautiful, well-appointed apartment in Colonia Del Valle. My favourite places within the block were the cafe at City Market, the superb Italian restaurant literally around the corner in Calle Matias Romero and on the same corner - Empanadas Argentinas! mmm Que rico!
In different directions you can walk to the Metro stations. Also check out the very modern shopping at Liverpool nearby and the food court on the top floor.