Where to start with price comparison site

Hi

I want to develop a price comparison site for a particular "product" (not really a product but best term I can come up with) and I don't believe a site for the same thing exists.

Basically I want the user to be able to put in a reference and then I pull prices from other sites and display them.

Thing is, I have no idea where to start Any tips on how you get prices from other sites would be great a long with anything else I should be aware of.

Thanks in advance

 

Im doing one of these
Making it from scratch and its a bit tricky in places
Sorry not relaly got anything to help you apart from plan it out on paper first!

 

Have you managed to get prices from other sites yet? If so, how do you go about that?

 

For that I'd use cron jobs of cURL + Regex

 

It depends on the sites you are going to be acquiring prices from and if they are are actively allowing you to do it. Generally there are 3 options subject to the product type and in order of preference:

1) XML file
2) Web Service
3) Screenscraping

If they are cooperating with you they should be able to tell you what they have available/ file structures etc

After this is bottomed out it is just then a case of setting up a time based job to run it periodically (cron job if you are stuck with using php)

 

So I need to contact the sites first then. What kinda thing do I say to them? Because I don't really want to reveal what it's for because they could easily take my idea!

 

Why would they? Presumably you are comparing pricing with their competitors so they are unlikely to want to advertise their competitors by setting up their own service.

The other option is to do screen scrapping however you then dont receive any commission from then for referring sales to them, it may breach the terms of use of their site and so opens you to being sued and they can take actions to prevent you from doing it. Also depending on what the product is you may have legal considerations - eg for insurance in the UK you would be in breach of the regulatory bodies rules by not having the insurers permission

To be honest, cant really help on what to say, who to approach without knowledge of exactly what it is you are doing - having to give advice blind here

 

Very good point I guess!

And screen scrapping sounds long winded/complicated and commission is one of the main aims of the site if I get it going.

I guess I'll just have to email a few sites and see what they have to offer.

Thanks

 

Screenscraping isnt that bad to do, the main pain is keeping it all up to date if they change how their site operates - large companies not an issue but smaller ones can be fairly unstable. Of cause it is large companies that are most likely to have XML feeds for the likes of Froogle or other price comparison sites. If it is something more complex like insurance then they will frequently have APIs already available.