Highly recommend staying at Marcela's place if you're in BA. From the first moments of communication to check out, everything went smoothly. It was our first time in Argentina, and we were very pleased with the location, the building and the safety of the apartment. It's only 2 blocks away from Santa Fe Ave, which is one of the main roads, whether you need a taxi or public transport, it will be easy to get where you're going. Botanical garden is almost at the footsteps. Palermo SoHo has great restaurants and it's only 5-10 min walk.
As far as the apartment itself, we found it to be very convenient for 2 people. It was clean, comfortable, and had everything we needed, including Sube card. Our week in BA was productive, thanks to a great wifi and numerous guidebooks at the apartment. I will definitely use Marcela's place again if I come back to Buenos Aires!