Custom Plugin Modification for Wordpress

MAX BUDGET = $50. We do have lots of FUTURE / Ongoing JOB for successful applicant. We need help to modify our custom plugin in wordpress for a car dealer system. This is a plugin for our client to issued warranties card, and a simple order invoicing system. unfortunately this plugin is in Indonesian Language. So local freelancer is preferred. but im open to any possibilities and willing to help the chosen freelancer understand the basic flow of system. DEMO: UN: temp PAS: 9a7TVui9ktq3 [login to view URL] Required Modification: 1. Limit Viewing per user. - Sub USERS only able to view / add / edit / delete their own list of order, and their own issued warranty. - Sub USERS only able to view: Product List and Warranty (Products) Menu. - Sub USERS does not have the capability to view Customer Database Menu. - Create Only One CENTRAL Admin Account that is able to access all menu's and capabilities. 2. Auto complete Form for Create New Order. - text field input fetch a list of "vehicle plate number" that are already stored in DB server. - When admin typed / selected the chosen vehicle plate number, it will automatically generate the customer name and contact number. Reference: [login to view URL] 3. Input Validation. - Vehicle Plate Number must be unique. - Code Label for product is 3 letter maximum, and must be unique. 4. Generate Warranty Invoice Format: [Product Label][YYMMDD] 5. Currency Format in Rp (for javascript calculation in add new order panel). Feel free to ask questions if something is not clear. This is an urgent project, and i will appreciate a FAST Turnaround time. ~3 days Max. Further explanation will be provided once a freelancer is hired. Thank you. Please write "DEVELOPER" at the beginning of your cover letter, to show that you've read and understand the whole project brief.