From my experience of opening a banco posta account here in Italy you need to be in the country and have a permesso / carte soggiorno (for non Italians) before they will accept you. The charges are low for Italy but with all banks here you need to get used to all the extra charges. (fee to transfer money to another account, fee to use a non poste cash machine, fee to pay bills, government tax to have a bank account ect….) for further information visit the web site at
www.poste.it
Banco posta does have its advantages over other banks as they are open until 7pm Mon – Fri and half a day on Saturday. (Reasonable size town / city) Normal banks are generally only open from 9 – 1400 hrs and closed on :) Saturday.
The only down side I have discovered so far is that if you wish to set up a direct debit for example to pay an mobile telephone bill automatically (mobile company 3) then you are unable to as Banco Poste is not considered a bank by some companies.
Hope this helps