Display Upsell Cart Hints and Invalid Coupon Messages in the cart
The extension adds two smart features that encourage the customer to increase his order value - the Upsell Cart Hints and the Invalid Coupon Message.
When the customer adds some items to her cart, and she is a few items short from getting a cross-tier discount, the extension will notify her about that. It will display an informative message in the cart (aka the Upsell Cart Hint) to explain to the customer what items are missing to accomplish the cross-tier discount.
The Invalid Coupon Messages work the same way, except that they show up when the cross-tier is bind to a coupon code.
Example #1: The cross-tier promotion is "Every three t-shirts for $50". The customer adds one t-shirt to the cart and goes to the cart, to review her order. The Upsell Cart Hint shows up in the cart saying, "Add 2 t-shirts to cart and get a set of 3 t-shirts for $50 only".
Example #2: The cross-tier promotion is "Get two bags with a 20% discount," and it has a coupon code bind to it. The customer adds a bag to the cart and applies the coupon code. The coupon is invalid because the customer doesn't have two bags in the cart,
so the "Invalid Coupon Message" shows up - "Add one bag to cart. Then try applying the coupon again. You should get the set of 2 bags with 20% discount."