database redesign and manipulation for wordpress site

We are seeking a redesign of a database for a portal site. We require an automatic table creation interface ( sign up ) with uniform content fields. i.e. on registering on the site, a member username and password will be created allowing the user to modify their personal details and they will be allocated a table to list their [login to view URL] product will have 12 fields plus multiple images. All members of this site will be selling the same type of item. we also require the ability to overwrite the product table by importing a standardised csv file we will require a script that will run via a cron job to import multiple csv files overwiting multiple client tables. full control of the tables to be overwritten and the csv files to use must be easily controled ( possibly via dat file modification) Further details and the site requiring modification will be given upon enquiry