woo commerce and creating buyer groups on a WordPress website

I am creating a website which is going to be a normal e-commerce responsive website using WordPress.

I have a request from the client and I needed some clarification on the subject.

For 3 different clients who log in using their usernames and passwords the wants all the commodity prices on the website to change.

To make it clearer:- If the price of a bottle of wine is $10 and this is on display to users who have not logged in. When a specific user logs in the price of wine goes from $8 .The changes take place throughout the website for all the products.

I hope this makes sense. I will be using woo-commerce but I haven't been able to find a plug-in that would let me do this. Is there a plugin or a way to do this. Please help.

via Chebli Mohamed