Pluses:
Sergio is responsive, it was very helpful when we needed anything during our stay.
Location is well-located in the city center. I recommend the supermarket Continente that is about 5 minutes from the flat. You are in the direct center in a few minutes.
There is more or less everything you might need in the flat.
The internet connection is good even for work.
Negatives:
There are just two very small windows in the flat. You may lack the daylight.
The flat is noisy. When you open that little window in the bedroom, you can hear someone's bathroom (with very disgusting noises) or smell from someone's kitchen, so you just keep it closed.
Humidity - despite opening the window next to the door 24/7, the flat is incredibly humid. I am not sure whether it's suitable for everyone because of the health.
Location - The flat is located in the Indian town. You may do not feel much safe there.
Checkin - We were waiting for about 30 or 40 minutes with our luggages on the street, which was not much pleasant.