Build Interactive Real-Estate Marketplace

I already have a partially-built codebase that covers the basic layout and some core functions. I now need it transformed into a fully-operational, interactive customer site centred on real-estate listings, with the ability to branch out into cars, furniture and similar physical goods... (Budget: $2 - $8 USD, Jobs: Backend Development, Database Management, eCommerce, Frontend Development, HTML, JavaScript, PHP, Web Development, Website Design)