The city of Florence has various different types of transport, and these tickets can be bought in the metro stations, at tobacco shops, and newsagents.
The single ticket is valid for 90 minutes from the moment it is validated. You should put it into the yellow machines on the buses to validate. The ticket costs 1,50€ (US$1.6).
4 Trip Ticket
This ticket costs 4,70€ (US$5.1), and can be shared among several people.
Agile 10 Card
This magnetic card is loaded with 10, 90-minute journeys. Just as with the 4 trip ticket, it can be shared among several people. The card costs 10€ (US$10.8).