It was a great place. I came to stay for a few days with two other friends. There was even a spare bedroom, so even enough space for four people. The contact with Pilar was very smooth. She was very helpful and kind and replied very fast. It would've been nice to see her in real life as well, but it was okay.
The main living room was a little bit smaller than expected, but it has everything you need.
A big plus is that there are windows and doors to ventilate. Apparently not all apartments have this. We also had a fan in every room, so that was nice.
The bathroom looked pretty clean, there is a bath tub with a shower.
About the location: we thought it was closer to the airport somehow. It's about an hour away. But the public transport is very easy. The metro station is two/three mins walking from the apartment. There is a direct line for Plaza Mayor etc (about 30mins ride) and for the airport with one transfer at the main bus station.
For us it was important to go for Mass. About five mins away there is a church where there is daily Mass. This was a great surprise since we couldn't find it via internet (Maps).
The neighborhood seemed pretty chill. Not very busy.
There are many restaurants and cafes.
We went to a Nicaraguan restaurant (Nicaragüita) around 10mins from the apartment, which was amazing! It's highly recommended! The people were nice, the food was great and it was not expensive.
A little thing that might be something to improve is to be able to store the luggage after checking out. But I understand that it's not easy and convenient when the apartment should be cleaned up for the next guests. Also it's not in the center, so you'd have to go back and. And Pilar did give me some options for storing in the center of Madrid.
Overall we had a great time and I would recommend the apartment.
Thank you Pilar!