Taxi booking system modifications (PHP)

We need some modifications to an existing PHP booking system at: [login to view URL] Below pickup time we need a new field that reads "Return Journey" with a checkbox. When this box is checked it needs to double the price of the calculation in total. This figure along with the "yes" or "no" value from the return journey should be pulled across through the stages and appear in the admin section on the order confirmation as well as being sent out on the confirmation emails. In the select an airport drop down I need two new airports adding, these are controlled in the backed where additional prices can be added for each area. This should be case of duplicating code and tables that already exist. The developer will be required to work on the files on their own server environment, we will not be giving access to our servers directly. ## Deliverables 1) Complete and fully-functional working program(s) in executable form as well as complete source code of all work done. 2) Deliverables must be in ready-to-run condition, as follows (depending on the nature of the deliverables): a) For web sites or other server-side deliverables intended to only ever exist in one place in the Buyer's environment--Deliverables must be installed by the Seller in ready-to-run condition in the Buyer's environment. b) For all others including desktop software or software the buyer intends to distribute: A software installation package that will install the software in ready-to-run condition on the platform(s) specified in this bid request. 3) All deliverables will be considered "work made for hire" under U.S. Copyright law. Buyer will receive exclusive and complete copyrights to all work purchased. (No GPL, GNU, 3rd party components, etc. unless all copyright ramifications are explained AND AGREED TO by the buyer on the site per the coder's Seller Legal Agreement). ## Platform PHP/MySql