You seems to be new on Freelancer as not having any rating. So, I'm not sure how you will be shortlisting.
I've a pretty good past experience as a web and desktop based development, with having good knowledge of implementing Amazon services, based on their published APIs as well as scraping.
To what I understand from your requirement, you need to have some information (say ASIN, SKU, Price, Description, Rating etc.), and like to have a CSV generated as a result. CSVs should be in compatible format to get uploaded on eBay and Magneto, to update their listings as well? Correct me if I'm wrong.
And yes, its not the only solution to scrap, but we can use Amazon's API services to get much information. So yes, I dont have any tool that can scrap or something, but guarantee you to provide feasible solution being familiar to the marketplace programming.
Do check my previous work in my profile, as well as comments and ratings that may help you in realizing my skills and providing quality solution
Cheers mate.