Visa to Enter Italy
Depending on your citizenship you may be required to apply for an entry visa to Italy. You can check if you need to apply for a visa at this website.
Tickets for public boat (vaporetto) transportation may be bought at ticket counters scattered through the city, along the channels, at the boat stops.
Please, be aware to have always a valid ticket when on board of a vaporetto. IF you have not purchased a ticket, please, tell it the sailor IMMEDIATELY on boarding to avoid discussions and penalties. Severe and frequent controls are made on board.
It could be advantageous to buy a cumulative ticket (validity 7 days) on your arrival (cost: 60 Euros). In such a case, remember to validate it every time you get a vaporetto.