Andrea's son Santiago welcomed us at the (late night) time of our arrival, and also checked us out. He made us feel safe to leave our valuables in the apartment while the cleaning lady came for her weekly visit. Andrea was very responsive to our emails when we had questions.
The apartment was tidy and very conveniently located near the metro stop, stores, supermarkets, and a movie theater.
The neighbourhood is very nice, tree-lined, very beautiful to walk around.
Our first time in Argentina, we were surprised that we could not throw toilet paper into the toilet (my first such experience), but we found that this is common in Buenos Aires - it was the case in many near-by restaurants. Another small point, for those sensitive to noise, is that there is little sound isolation both from the outside and the neighbours. There is a parking garage across the street with a beeping device every time a car comes out, and the people talking on the street are very audible on the first floor. But for those who sleep sound this will not make a big difference.
Overall, we were largely comfortable and found this apartment a nice home base for our two-week stay in Buenos Aires.