Tiered Shopping Cart Website

Project Brief: Client (Owner) provides printed products which are sold via Distributors to Retailers. Their current website can be described as an online store, and does not provide them with the ability to manage product and pricing effectively to the various Distributors - both of which vary based on the Distributor. Further, the current site does not allow them to easily cross-promote products. (Think: Amazon - people who looked at this, also bought that...) Ideally, the website would be visually appealing, standards compliant, easy to navigate and produce a great visitor experience. Enhancements like lightbox image effects, ajax page/cart updating are desired, but should not detract from the visitor experience. We really want a professional outcome. We wish to create a custom web application consisting of a multi-tiered role-based shopping cart system with the following features: Site Roles and Functions Administrator (Owner) Vendor (Distributor) Customer (Retailer) Administrators Will have the ability to manage the entire site with easy to use forms and reports to include managing carts, inventory, pricing, email notifications, site content, vendors and customers regardless of vendor/customer relationship. Administrator Functions: Administer a base inventory and apply individual price markup per product per vendor Create vendors Create vendor cart/site design (add logo, simple colors to unbranded website) Create customers and assign to vendor View and react to all orders with email notification system View reports on Vendor orders View reports on Customer orders View all orders and order history Edit Vendor and Customer orders Freeze Vendor or Customer accounts Delete Vendor or Customer accounts Edit Vendor or Customer accounts(reset password, billing info) Manage all site content to include, news, announcements and such Manage messages by Vendor(unique message only seen by logged in Vendor account) Manage messages by Customer(unique message only seen by logged in Vendor account) Manage advertisements to Vendors Manage advertisements to Customers Vendors Will have the ability to create and manage their own customers and assign pricing by item to individual customers. From the base inventory and pricing set by the site admin apply markup to individual customers by item. Create Customer View and react to Customer orders with email notification system View Reports on Customer orders Freeze Customer accounts Delete Customer accounts Edit Customer accounts(reset password, billing info et all) Edit Customer orders View orders and order history Manage messages by Customer(unique message only seen by logged in Customer account) Manage advertisements to Customers Customers Will have the ability to view and order products from their assigned Vendor only and maintain their account information. Create orders and receive email notification of orders and order status View orders and order history Edit billing, email and other customer specific account information View site FAQ and send email help queries View Site and Vendor messages View Site and Vendor specific advertisements Shopping Cart (Customer) Shopping cart with multiple vendors Role based customer shopping by vendor Themed cart based on vendor and customer* Pricing per vendor, customer, product Controlled access by customer to assigned vendor cart only Email notifications when order is placed to Customer, Vendor and Administrator Vendor interface should be accessed via subdomain or directory of main site, i.e., [login to view URL] or [login to view URL] (which would be a login page). Please let me know if there are any problems that arise because of this requirement. Shopping Cart (Public) Shopping Cart with Credit Card Gateway for Public Shoppers (those that are NOT customers who purchase through a Vendor portal) Same Email notifications to Administrator Ongoing Maintenance Agreement Please provide estimated pricing for project maintenance