Build a website

A website where users can visit,sign up and choose an ad category(online,offline) they want to advertise, then they'll choose sub-categories e.g newspaper, radio,yahoo ad etc . for any sub category that is chosen, user will go through a simple process to give details example is for newspaper, user will choose the newspaper from a selection uploaded by admin via the backend, day of ad,position of ad,size and colour of ad. all these data will have been entered into the backend by the admin so that every choice the user makes gives birth to other options with different pricings. User can repeat this process after which he will be shown his total cost and pay via a payment gateway or bank deposit. all these will be through a straightforward and simple process.