Magento developer shipping by vendor consultant

Closed - This job posting has been filled and work has been completed.

Job Description

I am a developer on a project and am stuck. I'm not looking for someone to do the project for me, but I am looking for someone to consult along the way with strong Magento development skills.

The site I am working on is sort of like an Amazon in that different vendors can list their product. We have an attribute "vendor" with an id tied to each product that a vendor has listed. Most of the site is already built but I am trying to separate out the items during checkout to calculate shipping separately according to each vendor's location. No extensions that I have looked into will do this for me accurately.

For example, in a user's cart there are three products, two with vendor attribute value of "1" and the last product with vendor attribute value of "2". I need shipping to be calculated for the two products with value "1" and the one product with value "2" separately, and also with the applicable vendor's origin address. I will also have to modify the template to make the separate shipping calculations appear to the customer. I am totally lost in doing this. Anyone who is confident that they know how to do this please apply!