Federico was a very nice host to us. Although we did not have much contact, he was very sensible to our times of arrival and departure to deliver and return the apartment keys.
The apartment is in an old building, but brand new in the inside. Very cozy and stylish, we could easily fit 4, but two of the beds were double beds, so if you have couples you can fit more people.
Kitchen was very small but had everything we needed: fridge, freezer, oven, cook-top and microwave.
Only one bathroom, which could in times be annoying, but we managed well.

Location was perfect: not in the noisy and crazy city center, but close enough, 10min away by bike or metro. Metro station two blocks away. Beach 4 blocks away.
Lots of grocery shops and supermarkets around. Restaurants too. Is a residential area, lots of locals and not much tourists.

We had too bikes stolen in the city, but the building had space for leaving the bikes inside during the night, which was very very important!