I am from Sao Paulo, but my husband is from Santos and during a long time he had to do this route: Santos – SP (jabaquara), so I think we can help you. I asked him and he said that there are two companies that do this route, the names of them are: Ultra and Expresso Brasileiro
From Jabaquara you must take another transportation to go to Itaim. I think is much easier to take a taxi. There is only one problem is more expensive. So if you really don’t want to spend more money take a bus. In this case you need to call to this number, 156, and ask about directions.
After you arrive in your rented accommodation to go to GRU airport you can go by taxi, but in this case is much more expensive. So I think is better you go to Congonha’s airport and from there you take a bus to GRU.
This bus departs from Avenida General Francisco Glicério, 369 (Shell gas station) and the one-way fare costs R$ 35 (around US$ 20). Just in case, here's their website (available in English and Spanish):
Estimated travel time to Guarulhos airport: 3 hours
HI, I recently was in Brazil on a cruse and i have 8h after ship coming to santos port .
I decide to go to the beach and spend 45 minutes to find the parking(it's free but in holidays there no place. When i go back to SaoPaulo i stopped to it in MacDonald on the beach and find a perfect safety parking which is free and available.