Oliver was a very good host. He speaks some English (and good Portuguese) so we communicated just fine.
There were some small communication problems during our emails to each other before we arrived (he ordered one small taxi for us even though we were 6 people, his lovely taxi friend Stella does not speak English; he said the taxi would cost 350 pesos and it cost only 100).
But he was so very friendly and helpful. He left a guide book for us, a bottle of wine and a subway card with 100 pesos on it!
When we had small problems with the place (air con not working when we arrived, toilets plugged up twice) he responded immediately, coming over to fix or sending a repairman. Very nice host.
His house is fantastic; it has the feel of a modern loft in NYC. It was spacious (especially the livingroom/kitchen with its high ceilings and skylight). Our family of 6 had the right amount of space (3 bedrooms and a big couch for our youngest one). There is a great patio to chill out on! (The stairs are steep so not recommended for the very old or very young). The plumbing was sensitive (plugged twice during our stay) so use toilet paper very sparingly!
Overall we loved Oliver's place, and recommend it highly to anyone wanting to stay in the lovely Palermo Soho area (great restaurants everywhere, high quality fashion shopping, cafes, green streets, big parks in easy walking distance - the Jardim Japonese and Rose Garden are really great!) Quiet yet fun neighborhood - loved this area). We recommend this place without reservations and would return in a second. It was one of the highlights of our trip to BA.