Price comparison profit notifier

General information for the business: Comparing deal prices for video games.
Kind of development: New program from scratch
Description of requirements/functionality: I want an application, not sure if it should be web based or desktop based at this time. The application could be a web scraper or a price comparison application.

It should scan periodically (Haven't decided on the interval frequency) for deals on different video games (any platform) based on a temperature of more than 500 degrees at Hot Uk Deals, on the following website : http://www.hotukdeals.com/.

With the deals for the video games obtained, it should compare the price of the deal with the price that the following company is willing to buy for cash at the following website : https://uk.webuy.com/.

If the deal price on Hot Uk Deals is less than the price that computer exchange is willing to buy for cash at https://uk.webuy.com/ it should notify me via e-mail. (This indicates that there is profit to be made).

I am not sure if it's possible to have this application run itself without me having to compile/run it manually, as i'd like it to automatically, periodically scan HUKD without coming across as a DDOS.
OS requirements: Windows
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