Game Item Trading / Buying Website - Advice Wanted!

So I am making a website that allows people to trade in-game items (games such as team fortress 2, etc) for other items, real money, etc. My question is do you thnk i should get an auction script for this or is there anything better out there? I cant afford a completely custom job at the moment so i do need "ready" solutions. Thoughts on ways to go, scripts, etc?

Have a look at Magento and the eMarketplace plugin....

cheers

olystyle

thanks for the links. I am leaning towards phpprobid tho.