My husband and I lived in Javier/Eze's apartment for around 4 months while we were traveling/working remotely in Buenos Aires, and we had a great experience. Their apartment is very conveniently located in Palermo - across the street from a supermarket (Disco - personal favorite in BA), around the corner from a great gym (Always Gym), the Botanical gardens, Santa Fe (where you can catch any bus) and tons of trendy restaurants.
For the amount of space, it is a great value for anyone looking to do short or long term. We both work remotely so strong internet is necessary, and we only had one day where we had any problems (which for Argentina, is stellar).
Javier is also very responsive and speaks excellent English. Thank you for the great experience!