Our hotel in Florence is very close to one of the stops of Hop-on-Hop-off bus (City Sightseeing Firenze red double-decker in particular).
Do we need to go to the bus terminal to buy the tickets, or we can buy them from the bus driver?
I sent several email to that company, but did not get any reply.
Thank you in advance for your help
The website you link answers your question in its FAQs, which is probably why it has not replied to your emails:
>13. Where can tickets be purchased?
Tickets can be purchased on our website, onboard our buses, from our ground staff where present, or in our Visitor Centres.<
So you can buy tickets either on the bus or from the ground staff if they are at the relevant stop. You can generally expect to find staff at the major tourist-attraction stops such as SMN railway station, Piazzale Michelangelo and suchlike..
But is the hop-on bus even worthwhile if you have no mobility issues? Central historical Florence is extremely compact, very walkable and safe to walk. As an example, it's less than 10 minutes' walk from Firenze Santa Maria Novella station to the Florence Cathedral...and only around 15 minutes' walk from the Duomo to the Pitti Palace. Hop-on buses, like all normal-sized buses, cannot even enter the Medieval streets in the city's historical centre. All the stops on both hop-on routes are outside the city's historical heart (look at the route map on http://www.firenze.city-sightseeing.it/eng/percorsi.html).
The only place which is more difficult to reach on foot (primarily because it's up a steep hill!) is Piazzale Michelangelo (and the ancient church of Abbazia di San Miniato al Monte nearby, which I strongly recommend). But buses 12 and 13 regularly leave from SMN station and go to Piazzale Michelangelo. Bus routes, times and details in English on the official site:
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