I had a nice stay at Zip Housing. My apartment was nicely decorated, comfortable, and well equipped. The building is close to the Escuela Militar metro station and there are lots of restaurants close by. I recommend a bakery and cafe called Brothaus, which is around the corner. The apartment has a very nice view of the mountains. Daniela, the host, was quick to respond to my queries and I felt well taken care of.
I would definitely recommend staying here, and hope to return.