Agriturismo or Villa

I was looking at SIXT as a rental company. Are they reliable? Also, should we rent the car from the Central Train Station location (since we will be taking a train in from Venice) or is there a reason we should rent from the airport location? Price looks to be the same.
 
Since you're arriving at the SMN train station, the location of SIXT at the train station is ideal. I just learned they are in the underground parking lot so if the rates are the same, it makes sense to just rent from there. Just be careful on driving OUT away from the ZTL area/historical center. You don't want to make wrong turns and go down a street that is considered within the ZTL because then you will receive a fine. Just ask for a map with a route marked on it from the rental counter if you can, so as you drive out you follow the suggested route. I think it is the one I've outlined below.

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Our flight is scheduled to arrive in Venice at 9:30am. Apparently the train station is a 20 minute bus ride from the airport. I read online that there is a ATVO AirPort Express bus they we can take direct to the train station. Is that our best option? Can we just purchase train tickets to Florence when we get to the station or is there a good reason to buy them in advance? My only concern with buying in advance would be if we got delayed and missed our scheduled train.
 
I would just wait until you get to the train station and buy your tickets then. Sometimes Trenitalia runs some special offers, but sometimes the conditions for those offers are pretty limited. SO you could take a look at the website and see if searching for your dates offers a discount or not (it will say so).. if not, then I would personally wait. That way, you can take the next bus and then next train at whatever time you arrive without being stressed out because of time and timetables that need to be met. You're coming in September, but the airlines and airports are a mess, with many delays (and lost luggage along the way), so I'd just plan for worst case scenario and that you do get delayed and then would miss a train. This way, just go with the flow! ;-) As for the car rental company, if you arrive an hour late (or early) for pick up, they never make a big deal but you definitely don't ant to stress about the train beforehand.
 
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