Susana is a very helpful and friendly host. When we arrived she already recommended us several good spots to visit and to eat at. The apartment is very clean and tidy and very well equipped, we were missing nothing; in fact we were expecting much less. The location of the apartment is very good; you reach plaza mayor in a few minutes by foot.
Nevertheless, the surroundings of the apartment are very very loud. Every night we woke up due to really incredible loud noise from the street. Not just a few people shouting something as they walk by but rather trucks and strange noise of unloading things. Apparently, in this area, they collect the garbage at around 3am in the morning, too. It felt like we had the truck directly next to our bed. We recommend earplugs.
As it is an old building, the apartment itself gets really cold. This is not much of an issue as long as you have the electric heater on at night ;)