Developer needed. Coupon code order only.

What I have is a physical product and each physical product has a different code. With that code only I want to give customers access to extra content. To have this ability should not be restricted to any groups.

I know how to put the codes with PhpMyAdmin but I find the interface of Hikashop too complicated for the end user. I don't want any "add to cart", "proceed to checkout", shipping etc. options. Just go to the product and enter the coupon code and then its done.

I guess simple option like that will be more complicated than I though.

I own the business version of the Hikashop.

If you have an idea how to do this and price what it costs. Please leave the contact details here.