I am writing to request the opening of a bank account with your institution. 1. Look into granting financial power of attorney for limited transactions.Sample cover letter to accompany Direct Deposit Authorization form. Just fill in the information below, and send to your employer's payroll department. Date. Authorize someone to conduct transactions on your behalf with this sample of an authorization letter for a bank. An applicant may print the image (e.g. , bank statement) and provide the printed copy when presenting documentation.