Build Custom WordPress Plugin

We need you to build a CUSTOM (Not download someone else's plugin and customize it) plugin for WordPress that can be installed as a standalone for some of our clients. This plugin should be compatible with the latest WordPress release. Features required on this plugin: *Online registration. **Initial self registration, would need to be approved by admin. Credit Card Payment accepted at time of registration, refunded in rare case of not being approved. **New member would upload business information into a form, address, web and social, description and upload logo / images. **Automated email confirmation / Thank you messages. **Automated reminders to renew annual membership. **Member data should be available to export to spreadsheet and use **Business Directory **Auto populated with content supplied from all approved members registrations. **Can be edited by the approved member / business owner **Mailchimp / Constant Contact integration: **New members auto added to list ** A page with a list of members (Similar to a CRM) where we can see emails, addresses, etc, and be able to export it into Excel. Again, this is a plugin built from scratch. Our company will install this plugin in several of our client's website and would like to build a relationship with someone here for an ongoing maintenance and upgrades to the plugin. ** Please, only bid on this project if you have the knowledge and experience in developing WordPress plugins.