Amazon automatic Price Fixer

I have store on the amazon and I need a little application to fix the prices automatically. What I need for this app: I will enter the sku or lsiting ids this application need to check the listing every 10-20 minutes and it needs to change the price one cent below to the buy box price or if I m not in the box, it should be able to change it 1 cent or 10 cent (I want to be able to change this parameter too) from the cheapest competitor price I will make the payment in full once I see the application working fine.