Alteration to booking process - Online reservations

I need some alterations done to existing code for my realime reservations platform. Most of the code is wrtten and working and tables set up and functional however I need the booking process and booking search return results to be changed and a few additional items added such as optional and mandatory additional charges displayed and calculted into the system where they apply to a venue. There are two folders where these changes are required for search page changes and it it involves changing a common set of 4 pages that are used by all users being the booking process pages. The three different user types are a "general user" off the web and two types of "administrator users" (two folders). All three types of user use the same booking pages. There are two types of establishments that can be booked. 1. Is when an establishment is sold on a "per room" basis 2. Is when an establishment is sold on a "per unit basis". In the case of item no 2 above, some parameters in the booking process are not required to be selected by the user as they are booking the whole unit (e.g. a house that has 5 rooms) and therefore do not need to choose room types as they would do in a hotel, nor do they need to allocate people to those rooms HOWEVER the room names for "per unit" type of establishment and number of people are hidden parameters that need to be used for the booking process to work so those parameters are required to be used throughout... I have atached a document with screen shots of what I need done however I think one on one discussion will be neccesarry as a few programers have worked on the system and so some delving intot he code will need to be done in order to find other pages that are "include_once" etc. Some javascript will need to be written in order to provide client side calculations on the fly.... ALL WORK TO BE DONE ON MY SERVER....