We had a great experience staying with Guillermo! He is an excellent host, always responded very quickly, and helped us out with anything we needed.
The apartment is really lovely, and in an excellent location. We stayed for one month, as we were working on a volunteering project in Buenos Aires, and the location of the apartment is perfect. Within walking distance from buses, subte, bars and restaurants.
I can only recommend Guillermo, and would definitely stay with him again!