public ActionResult BillingInfo(string customerId)
{
int id = 0;
Int32.TryParse(customerId, out id);
CustomerDT customer = CustomersManager.GetCustomer(id);
List <InvoiceDT> invoices = CustomersManager.GetCustomerInvoices(id);
decimal balance = CustomersManager.GetCustomerBalance(id);
string cardType = string.Empty;
ViewBag.Customer = customer;
ViewBag.Invoices = invoices;
ViewBag.Balance = balance;
ViewBag.CardNumber = CustomersManager.GetLastFourDigitCreditCards(customer.Id, out cardType);
ViewBag.CardType = cardType;
return(View());
}