title: How do I get quote totals before saving payment method?
body: <p>I am trying to create a one step checkout, but in the checkout page I have problem with order review part . When I select a payment method for example "cash on deliver" has 5$ extra, or "checkorder" has %4 discount or "credit card payment" adds extra to the order total. 
  I need a way to calculate the discounts before saving the payment method. Any suggestion?</p>