We arranged for our son, finishing university age, to visit Buenos Aires - to see his sister and become familiar with another Latin American city/country - coming from Lima himself. Claudia and and her assistant were very welcoming in arranging for check-in and giving advice on the neighborhood and Buenos Aires.
The apartment was very nice, a more traditional style with windows onto the street 4th floor (?). The Monserrat neighborhood has easy access to Metro and SubT and is within walking distance of government center, the plaza Mayor, and commercial areas. It is not as upscale as you would find in the more expensive Palermo and Recoleto areas.