Grisel provided us with a lot of information prior to and during our stay which was very helpful. San Telmo is a lively part of town with lots of bars and is close to some tourist attractions. BA is HUGE, so it would be impossible to find a place close to everything.
The actual apartment is very nice and charming, but old. We found one of the beds too small for two people. One of the four of us had to sleep on the couch (not a big deal for our family). On a very hot Summer day, one of the AC units did not work very well, so half of the apartment was almost unbearably warm. Luckily for us, that was only one day during our visit. I would still recommend staying here :)