Hello,
I understand that you want a superb and professional solution for your amazon project. I also understand that you wish to upload a file containing links to products online at amazon and check their prices. However, does the uploaded file contain a price with each item, then it connects to the link and checks for a new price? OR do you want to have the application check each link every X amount of minutes or whatever and check if the price has been updated? I could do this with ease for you if you would be willing to fill me in on a bit more information. I made a price checker in the past for amazon but I'm not sure it's the same kind of project as yours. I have been developing professional automated solutions for the past 6 years now, so I a am more than capable of creating a perfect solution just for you.