Documents

For individual people:
A recently issued document or identity card, which testifies the residence.

For legal entities:
Deed of association, statute, authority to sign, maybe translated in Italian by a translator, who is registered in a register of the tribunal or with an endorsement of the Italian embassy from abroad.

Self-certification signed in the relevant form , if the non resident, disposing of the qualifications, intends to avail himself/herself of the non taxability.

Activity

All the deposits, cash, bank cheque or bank draft, issued on the Italian territory have to be accompanied by a self-certification or a customs declaration, which is necessary to testify the provenance of the payment. The alternative documentation is only accepted if it demonstrates the certain provenance of the money (for example a notarial deed, a deed of the succession or an invoice).
The issue of other services, which are connected with the current account (cheque book, credit card or the delegations of the payment), makes the acquisition of a Fiscal Code inevitable, which will be issued by the Italian revenue authorities.