We had a personal tour with Fritz, our van driver and tour guide. Fritz was very informative and humorous. We saw the highlights of the city in four hours. I would recommend doing this your first day as a way of planning the rest of your vacation.
An excellent tour of the city with an incredibly knowledgeable and entertaining driver/guide unfortunately I didn't remember his name!. The tour stopped at places that we wouldn't otherwise have visited like the Mission de Asis and Twin Peaks with its incredible views and was a great introduction to the city on our first day. Just the right length too.
Great trip and the guide was fabulous. He was knowledgable as well. I recommend everyone to take this city tour. It covers most of the places with a three hours span.