My family is taking a bus from Firenze to Castello di Verrazzano and was told to get off the bus at the Greti bus stop. Is there a taxi service from the bus stop the castle?
I don't know if there is a taxi, but their tasting room is about two blocks from the bus stop. You pass it on the way. They may be able to call a taxi for you. The actual winery is about a mile up the road. 30-40 minute leisurely walk.
One of my favorite wineries in Tuscany. Do have lunch, you won't be disappointed.