Used books posting website

This is just to get an estimated quote for the project. I am looking for a clone of books4exchange . com Ajax is preferable where possible (filling forms, looking for courses, titles, etc). User should also be able to search for books according to their university course code. Unlike books4exchange, we will provide this service for free so no ecommerce sort of engine is needed, but should keep it scalable so in can be integrated if needed in the future. THIS IS NOT PART OF THE PROJECT RIGHT NOW, BUT SOLUTION SHOULD BE SCALABLE TO IMPLMENT THE FOLLOWING IN THE FUTURE: Ability to grab xml feeds from few independant bookstores for a price comparison to a new book. So if I'm looking at "Principals of Economics" used book for example, there should be a price displayed for a new one from an external xml feed. Please bid ONLY if you have done something of this nature already. We are limited on budget. Please send us your offers with a portfolio of similar projects. Thanks