I've created many custom scrapers for customers over the years (retailmenot included), and although I don't have any seller feedback (I'm just starting out here on freelancer.com), I can assure you that it will be a professional job. I'll be using VB.NET and it will take me around one day to complete the task. I will also provide a demo for you before you pay, so that you can see it's working. If this sounds satisfactory then send a PM and I'll get started.