Thanks Rb,
It's worth noting that 830 (Galeria Arroyo) is an auction house so the collection changes 100% from month to month. There are about five days prior to each auction when it is possible to view the paintings.
Once in a while the girl at the desk doesn't accept the $ for a catalog, but there is a sign that notes the price is $5 pesos. I have paid more often than not.
I suggest anyone who does go to view this month's collection pay some attention the the works by Manuel Claro Bettinelli. The base prices are remarkably low compared to most of the other artworks. Bettinelli died in 2005 and, since his death, his works have been offered more frequently at the better art auctions in BA.
One of the galleries very close to Arroyo has a great collection and decent prices. They also have several "locales" in the galeria across the street (at the corner of Suipacha). But before anyone buys any paintings from any of them, please let me know the name of the artist(s) you like. I may be able to connect you with a "wholesale" dealer who may have works by the same artists for at least 50% less.