Salesforce Developer to help build a Visualforce Page

Need a Salesforce developer to help me and my team create a custom Visualforce page. The goal is to allow users to associate multiple Accounts with Activities through the Opportunity "create a new activity" quick create action. A lot of ground work has already been done, such as the creation of two junction objects that successfully allow activities to be associated to multiple accounts. The current challenge is to allow users to select Accounts from a searchable list when creating a new Activity, specifically from an Opportunity quick action.