Price Comparison from my site against another site - simple or complex?

Say I wanted to compare prices of the same product from other retailers.
 
Obviously it would require a check everyday of their price and then updating competitors price in database so that it can be displayed to customer.
 
But is there any way of automating this?
 
(ie. Read competitor webpage, search for text WHERE item is named whatever and Price is LIKE whatever price and return this and display it)
 
Or is that over-simplifying a complex problem?
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