We stayed for 5 days in Buenos Aires at Florencia's place. The apartment is in a great location close to the metro, supermarkets and cafés. You can get to almost every part of the city within very short time. The apartment is in a safe and nice area where you don't have to worry about security. The apartment itself has everything you need for a longer stay. Nice kitchen, Apple TV/Netflix (what we didn't use because there is so much to see), books, great decoration, lift, aircon. etc.
After a great introduction with lots of information on activities, restaurants and cafes, Florencia was very helpful during our stay. Whenever you have questions or need recommendations she has valuable tips for you and answers very quickly. She and her husband are absolutely reliable and very attentive and far above expectations.
Therefore if you go go Buenos Aires stay at their place.