Design a script

I need a web based script developed that can reprice amazon listings.

Key points:-
Must connect with amazon API
Must collect listing information from amazon
Csv import and export functionality
Email price change reports
Multiple user accounts with signup form and integrated billing
Multiple amazon market places per account
Configurable time schedule per account
Configurable admin panel for account restrictions
Static web pages configurable through back end


Imported Fields required:
Product SKU
ASIN
Product title
Current sell price
Category
Product ranking
Seller rank in terms of price
Item Condition
country listed on / account name

Customer fields required:
Minimum price
Maximum price
Pricing rule (% or fixed price)
Amount of difference (positive or negative number) ie 1p cheaper than cheapest or 2% more expensive than cheapest


Software will be owned by us but you will be kept on board for maintenance/changes and developments as and when they are needed/happen. You will be required to handover a fully working system and rectify any problems that may be in the system. Developments will be arranged separately with yourself but must be reasonable in charges.

There are plans to expand to other market places so this project will grow and there is long term income available as well.