I highly recommend Cecilia's flat in Lastarria. The location is amazing — hands down the best neighbourhood in Santiago: pretty, cool, charming, lively, close to everything, with dozens of little restaurants and cafés with lovely terraces. There's also a great bakery just around the corner (and I'm French, I know what I'm talking about! ;). The flat's only walking distance to the city centre, Bellas Artes, Barrio Italia, Bellavista, and several parks. The subway station is also just there if you need more, and wants to lose yourself in Santiago.
The flat itself is great, spacious and luminous, very quiet, with a nice balcony, a bathtub, and a very comfortable bed: the perfect home to relax, read, and rest before going back outside to explore the city.
Cecilia and Alejandro are responsive, generous with their time, and kind. They have been extremely helpful at every occasion, and very patient with my terrible, terrible Spanish skills — that, in itself, is a proof of sainthood! :)
Thank you so much for everything.