I spent a month at Carolina's place, which was an excellent choice for a solo traveler. It has all the things you need to live, cook some breakfast etc. The area is very safe and there are many restaurants, two metro lines not that far away and many buses to go around the city (you'll need those). No washing machine but there's a laundry service just on the corner and it's very cheap. The church on the opposite side of the street is not a hassle as they use bells maybe once per day.
Overall a great experience and I know where I'm staying if I ever come back to Buenos Aires again!