Excellent location very close to La Latina metro station, a 5 minute walk to Tirso de Molina (and Lidl & Carrefor). Most of the things you want to see in Madrid are therefore close at hand and indeed, walkable when not carrying luggage.
On the whole, the apartment was good but note that there is no window in the bedroom. This did not bother me but some may find it unsettling; it does have the advantage of not hearing people walking by late on Saturday night after they have had too much to drink.
I was not expecting it but the building does have a small elevator.