Classifieds site

I am looking for a classifieds site that uses the same kind of script as 68classifieds or itechclassifieds. The site must have the end user in mind always and be optimised for search engines. Basically I don't want a massive listings site on the page but something easy to navigate through a internal search engine referencing a DB. The home page will have a little area for new classifieds but the design must be very minimal and simplistic. The homepage will link to another page that has a listing like those seen on [login to view URL] I need a reliable developer and one that has experience with these projects to date so if you don't have particular web2.0 references then don't bid. Thanks Wotcorp