This is for a non-profit website where additional donations should be encouraged along with ticket orders. I have already set up the donation as a product with drop-down values to establish the donation amount.

If a person has a donation in their cart, I want to display a brief thank you message on the shopping cart page that's shown before checkout. If they don't have a donation in their cart, I want to display a link to the product page for the donation.

I don't want these to display as sideboxes, but rather within the main shopping cart display table.

Thank you for any suggestions.