We stayed for 6 nights at Lina's place and it was simply wonderful !
The place is sooo central, few min. walking distance from all the points of interest in Madrid. The apartment is very nice, clean and very quiet although it is very central.
It has all one need + AC + a washing machine :-)
Just out of the door there are 2 supermarkets with fresh products which helped us make nice breakfasts at home. The apartment is on the 4th. floor with 2 elevators in a nice and clean building. Lina was very kind and responsive from the beginning and she really cares about her guests.
If the place is free - just book it !!!