Use an existing template for car rental and modify the booking section

Hello, We are looking for someone very capable in Wordpress coding. For our super-low-cost car rental service we are about to launch, we would like to use this existing theme found on Themeforest: [login to view URL] The theme can be used as is (just minor color changes to be done, and inserting our logo, texts, etc...).However, the booking/pricing part must be modified. We would like to have a dynamic pricing of the cars available. All the details can be read in the word file attached to the project. All the modifications mentioned in the word file must be accessible and be done EASILY by the administrator. Also, we need to be able to add/remove several different options for the cars, such as GPS, baby seat at additionnal costs. And for example, if the car is CLEANED inside before they return it, by the client, there is a discount! (valid only for 14 days rental or more), and so on... We do not need any "blog", just maybe a NEWS page. We need a plugin that makes a pop-up window when the site loads and asks for an e-mail address before entering the site. If they provide a valid e-mail address and phone and register, they get a discount of 5.- for their next booking. WPML or any FREE multi language plugin must be installed and deployed as well. This plugin does NOT have to translate. We will provide the exact texts in all 3 language. An example of website and the booking system can be seen at [login to view URL] . Thank you for your bids, and please, only bid if you are able to do this exactly as asked, and AFTER you have read the word file. Thank you!!