Develop a custom registration, order process and basic admin functions for WordPress website

I'm looking to add a custom registration and basic order process with additional admin functions to support a WordPress site. Whats custom is that a new user when starting the registration process will submit an ID number which will pre-populate the registration form with their registration data. The data that populated the form will be imported into the site via an upload process in admin. The user will then be able to edit and update the data in the registration form. When the user submits the registration form, the data will be saved in a separate table as a completed registration and WILL NOT overwrite the original data. This registration data should be accessible from admin to edit, view, update, and export. The order process: Registered users will have two options to order the user will select one of two options and that data will be submitted via email to a person that will process the order. A record of the order will need to be captured. Upon subsequent login, users will be able to submit additional orders. Admin Functions: Ability to upload the pre-population database. The upload will overwrite the existing data. Edit, view, and export all registered user data Edit, view and export order data Please include the term "custom WP" in your proposal to be considered. Preference will be given freelancers that have created something similar and can show examples.