amazon API solution to prices

Project Description: We work for a company involved in the retail industry in the US and UK. We need solutions to check prices of products in a major marketplace. In this case we will use amazon I am looking for a web-based amazon API tool that does the following: I upload a list of EAN codes in CSV, and the API tool will look-up what is the cheapest price for each reference, but only if it is sold by amazon or at least fulfilled by amazon, and it is currently in stock (even with a 2 day fulfillment delay). The results are to be downloadable in a CSV file. - The tool must operate within the allowable API calls-per-minute limitations. - We need to be able to upload a large list of references to run automatically every 24 hours. So the tool should be set to auto-launch the list at a pre-designated launch hour, and, I want to be able to change the launch hour when needed. - Important: the tool must not get stuck on a bad line that returns an error. it should skip that line and continue processing the rest of the lines. - Although the main purpose is to lookup the price (lowest price), The tool needs to be able to lookup the following additional values: (column b) sales rank (column c) category. there should be checkboxes to activate/deactivate these additional/optional fields. - The tool will be hosted on my cloud-based web server. I will provide amazon API credentials. The tool needs to function properly all year long. Therefore I am looking for someone who is committed to be available to intervene in case the tool ceases to function properly. I am willing to pay (in addition to the cost of this project) an ongoing relationship fee of $10 USD per month for a commitment to make sure this API solution keeps functioning properly Thanks