Please be aware that Form 1040NR is not considered a valid return unless it is signed. If you have someone prepare your tax return, you are still responsible for the correctness of the return. You can have an agent (CPA or other tax professional) in the United States prepare and sign your return if you are not able to do so for one of the following reasons.
A return that is prepared and signed by an agent must be accompanied by a power of attorney that specifically authorizes the representative to sign your return. Form 2848 can be used for this purpose.
Realize that the IRS does not allow e-filing for 1040NR returns. They must be paper filed. However, the state of Arizona does allow e-filing (upon signature of the efile authorization form).