Build online market

building online market ,meet the sellers with buyers for new and used products for everything like cars, real-states, electronics, pets and everything and the seller write a description for the product and contact data like e mail and telephone no. and the buyer ca describe what he need and the contact data too ( for example [login to view URL]) starting by country than city than category and under each category subcategories, I can add categories and subcategories as much as I can. the add is published for free for certain time I can change it whenever I need, after that time if the seller want to extend the add he will bay a value of money electronically using any type of credit cards, the value will generated automatically depending on the value of the product, also the site must have a places for adds I can sell it in each page, I need also a search engine also I need the users to register by name e mail and telephone no. to send information about the add like how many persons looks for his add