Database Driven site - online payments a must

I am looking for an initial site creation of a job search/posting site that will encompass 4 areas of the UK . These 4 areas must will be seperate sites but all running from the same backend database. They will have identical looks seperated only by logo/colours (examples available). The functionality will be as such. 1.) users must be able to search the site for jobs posted by users. Only subscription users may post jobs. 2.) subscription users must be able to either post on a monthly account or an individual post account. 3.) payment for the account type will be taken/made online via a payment gateway. 4.) global admin control (updating users, search fields, catagories etc) this is a basic over view only. The Bottom line is a lot of user account managment/creation, a great search system and online payment are required. This job is aimed at UK developers. ## Deliverables 1.) Complete a fully functional site encompassing the following features. a.) payment system for different account types through agreed payment gateway. b.) user account creation (multiple variations of account type) c.) User control pannel (the ability for a user to add/remove/edit jobs and personal details) d.) global administration system - the ability for admins to control the 4 sites and how users access the 4 sites, this includes user mangment, job editing/adding/removal, user details editing, global site prefence editing (drop down menus for search strings etc) e.) a modular database design including global data - data that all 4 sites find common (search catagories for or user data example) site specific data such as individual jobs - which should only appear on one site f.) a database design that will allow for additional sites/database's to be added at a later date without a complete re-design g.) site layout design (this is open to negatiation as basic layouts logo design ideas exist) h.) a search facilitie in each site that will only allow the searching of that individual sights records - yet takes parameters from a global database. i.) an email alerting system and auto enable/disable feature of accounts once "credit" has been used up j.) Site must be vewible the same in both IE6+ and Firefox for Windows and Unix based operating systems (including Mac OS) ## Platform a unix based operating system, with php/mysql (or postgres) and css No flash or propritary tools.