I have read all the other reviews and I can't match the reviews with the apartment my family stayed in.
The main issues we had were cleanliness, poor functioning shower, and non-functional washing machine.
When we arrived the flat was covered in black street dust. This covered the tables, kitchen surfaces, floor and seats. Within a few steps our feet were black and we had to wash our children's feet (after they had showered) and carry them to their beds. After we cleaned for over two hours the place was better. I understand that a flat overlooking the street will get dirty, but the level of dirt was like it had not been cleaned or lived in for weeks.
Isabel did offer to send the cleaner again, but as we had spent our time cleaning it seemed little point.
Generally the whole place was shabby and needed a thorough clean. The kitchen was also dirty with cockroaches and cobwebs in the cupboards. Cockroaches are not unexpected but on top of the general uncleanliness of the place, this just added to the cleaning we had to do (we washed all dishes and cutlery). During our stay the building was sprayed for cockroaches (we were not advised of this). The pans in the kitchen were damaged with the powder coat flaking off inside.
The shower head was broken so just produced a hose jet. The water however was hot and constant.
The inclusion of a washing machine was one of the reasons we choose this apartment and it was non-functional. It was old and had rust inside. When we did a test run with a towel it failed to run twice, and on the third try it leaked water all over the floor. The towel was soaked and no cleaner than before. We had to pay a significant amount of money to have our clothes laundered (we are a family of 4).
On the plus side, the flat is as the pictures, although now tatty. The air-conditioning worked well, good hot water, good location near to shops, bus routes, and metro. A good 15 minute walk to the obelisk.
We had 8 nights in this flat and it was the worst accommodation we have stayed in our 1.5 month stay in Chile and Argentina. I expect it is likely you could find better places for the same cost. Overall the place was ok, once clean, but not recommended.