I'm setting up an e-commerce site for a client who wants his customers to agree to a disclaimer before they order certain projects. He would prefer the simplicity of a service like Google Checkout or 1ShoppingCart where the actual purchase page is hosted outside the site and all that needs to be done on the main website is post "Add to Cart" links.

The problem is that none of the hosted shopping card solutions seem to allow for custom disclaimers that a customer must agree to right before their card is charged. It's easy to make customers agree to a disclaimer on the home site before they click over to the shopping site, but that will discourage some people from buying.

What my client wants is for a disclaimer to appear on the payment page right before the "Charge and Process" button. The customer would have to click a checkbox saying "I have read and acknowledge the terms and conditions" or something like that before they could click the Charge and Process button. That way the disclaimer is presented after the person has gone through all the rest of the payment process and they would be less likely to back down.

Is there any hosted shopping cart service that can do this or should I just give WP-Ecommerce a try (this is a Wordpress site)? Thanks for any info.