Hi I am travelling from Florence to San Gimignano on May 2 this year and back again May 10. I believe the number 130 bus stops right by my hotel in San Gimignano. What is the quickest/cheapest way to do this trip and do I book in advance (I wont know the exact times in advance so would need to be a day ticket) or book on the day and where do I pay? I don't mind train on bus but not paying for taxi or car hire.