prices per customer

Hi,
I have a problem with a site I am doing it’s basically a Zen cart shop. The client only wants his customers to place orders online the payment etc will be done through his normal accountancy. I turned on hide prices until logged in. At this point I need each customer to see their prices.
There are 250 products and a customer base of around about 250, but each customer could have different prices for each product many would buy at the default price. There is a default price for each product but he gives them variable discounts off each product they take. So, I need to be able to display to the customer once they have logged in their prices and once the order has been placed total it as normal in Zen cart. In the admin area of Zen cart I need to able to adjust the discount per product per customer. Is it possible to have some php script that will calculate on the fly the prices for each customer based on discount from default price for each product.
Can anyone please advise on how to do this?
Thanks
Ian

You would need to write a ton of software to manage these 62,500 price permutations.

No, and yes.

You can assign customers to groups and each group can have it's own pricing discount, but all see the same price in the product listing and info page. The group-specific discount is taken at checkout.

Is it possible to have some php script that will calculate on the fly the prices for each customer based on discount from default price for each product.

Sure, but it would be a major job. This mod does something like what you want, but for only two groups.

http://www.zen-cart.com/index.php?main_page=product_contrib_info&products_id=166

Thanks for the replies, although I was hoping it would be a simple request looks as if it's not :(
I thought an additional table in the database with customer id, product name, and discount would work. Then on the fly see if product listed against the customer calculate the new price otherwise display the default price.
Any other suggestions would be grateful, as I need to crack this somehow.