Daniela's apartment is very charming and nice. The spot is in a good location for exploring El Retiro Park and is about a 20 to 30 minute subway ride and about 40 to 50 minute walk to Gran Via for all the touristy places you may want to visit. There are some nice restaurants nearby as well for you to explore some spanish meals in a more "local" area.
Daniela herself is a very charming and attentive host and was always super responsive during my stay in her home.