Before you commented out or removed the echo statement, on your confirmation page (the page you want the coupon field to show up in), did it show CHECK_OUT_GET_PAYMENT_METHOD? If so you need to backtrack and figure out where things went wrong. Start by going to administrator/components/com_virtuemart/html/basket.php and at the very end of the file, make sure the coupon code template is not commented out. Then go to your shopping cart and you should see the coupon code field on every shopping cart page.
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