Internal Staff Portal with ERP APIs

I want to consolidate our day-to-day operations into one secure, browser-based portal. The focus is internal staff management: every division should be able to log in, track tasks, chat in real time, submit... (Budget: $8 - $15 USD, Jobs: API Development, Database Management, ERP, Mobile App Development, Project Management, Security, Software Architecture, Software Development, Web Development, Workflow Automation)