Build a Wordpress Theme that will act as a Client Product Ordering Portal

Beginning in the next few months we will require a skilled, experienced and professional freelancer/team to create a basic Web based ordering portal for our clients to use when requiring one of our products/services for events they intend to participate in. The plan is to create this portal as a WordPress theme that we can re-use on multiple WordPress installations for different clients. The idea is that the user will be able to create a new "event" on the "Create Page" and using a number of customizable forms they can select a number of options/inclusions they require for that particular event. Once the event is generated from the "Create Page" it will then populate under the "Events Page". Within the Events page users can then view all current, upcoming and previously created events all sorted in chronological order based on the event date selected when creating the event. Also within the "Events Page" users can edit information previously entered for the event in the "Create Page" as well as submit feedback and upload images specific to each event. When ever a user(client) creates/edits an event a notification email is automatically generated and sent to a specified email address. The theme itself must allow for building custom forms that would include but not limited too; drop down selections and even selectable symbols that would represent different product options. These symbols need to be customizable whether by uploading .pngs for each selectable option symbol or by some other means. The custom forms should also allow for an option to allocate a cost to each selection so that clients can track how much money they are likely to spend on each event based on the selections they've made. No money transactions will be made over the portal. The them must also allow for uploading custom logos in the top header section, so that they can be changed for dealing with different Clients/Companies. This will also mean the highlight colour of the them must be customizable so to match each client company branding. Each user from each company/client should be able to create a user account so that all event creation and modification can be tracked by each user. We are happy for the selected freelancer to use common WordPress plugins such as wooCommerce and Contact Form 7 as long as it can be customized to suit out needs. You will be provided with all design assets when required our requested by you. Your English communication skills must be good to ensure for fast and effective turnaround on issues or required changes.