After checking a number of sources includng Tripadvisor, I selected Buenos Tours for the half day Recoleta tour. And this was an excellent pick.
The sign up process on their website is very good and also provides links to other information and resources about Buenos Aires.
Jessica arrived promptly at the appointed hour at our hotel in Recoleta and we took a cab to Plaza San Martin. From there we walked around the area and then headed back to Recoleta. We learned a lot about the areas we were passing through and got a broader perspective on Buenos Aires and its history. A nice touch was a stop at La Biela, a coffee shop with a lot of history and some interesting locals enjoying the place. We concluded with the Recoleta cemetary where history abounds. Jessica was of great help in locating and describing the most important features and locations there.
On a walk like this a guide is a must for two reasons. First, a do it yourself walk with your head in a guidebook wouldn't come near to gaining an understanding of the locale. And second, there is a lot of petty crime, and some not so petty, in Buenos Aires. Having a guide with local knowledge provides a buffer to that.
High marks for Buenos Tours.More