We arrive at Venice by train on 19 September, and leave two days later for Assisi, with connection in Venice. The Trenitalia website indicates it's a Frecciargento from Venice to Florence, then connect to a Regionale from Florence to Assisi. Should we prepurchase the tickets for the Frecciargento now before we leave home, or buy them at the station in Venice when we get there? Thanks.
The ONLY reason to purchase early is to take advantage of discounts that may be available but those tickets come with limitation so be aware of that. Second do not buy Regional train tickets on the web as they have limitations. Buy Regional tickets day of travel as they are never discounted.
I'll be doing that Venice to Florence run in 3 weeks. I booked my ticket couple months ago when the schedule was posted and got it for 19 euro.