Eurail passes will have promotional offers, typically during the early Spring and late Fall. Otherwise pricing is standardized for rail passes and all legitimate vendors must sell passes at the same price.
In terms of different types of passes, there are discounts for youths, children or for groups of 2 or more people traveling together. Look for the Youth Pass or Saver Pass options.
Discounted train tickets for Italy will be in the form of promotional fares that are released throughout the year and based on availability. Travelers who sign up for our newsletter are notified in advance of upcoming promotions so they can book early when there is greater availability.