Maria has a decent place in Chamberi. There are 4 people in total (a bit packed), and she was always in the house, checking whatever you do.
As I need to work from the house, she was keep entering the room, checking if my pc charger was connected and asking to take it out to save energy (I needed for my job and my pc died otherwise). Overall, it was very stressing (you had to lock the door with 3 system every time you go down, even for a coffee)
I would suggest only as a place to sleep in the night and for a very short term