Ask HN: Does anything like this exists?

I am a n00b when it comes to web development. I want to know if some web framework to do the following exists or not.

1) I want to create a site where users can decide, from where do they want to buy a particular service. I wont be selling any service but only showing them the lowest prices from particular firms selling that service. Just to give you a better idea, I will have an excel sheet with the prices from each firm.

2) Users on finding the best prices for the service can select and make the payment online through some payment gateway.

This is all that I want. Or if there's any script already out there which takes care of data retrieval of prices for each firm as well as payment gateway.

Any input that you might provide will be greatly appreciated.