Secure Multi-Firm CRM MVP

I need an MVP web application that lets multiple firms log in, manage only their own clients, and never see data from any other firm. In this first cut the only functionality staff require is the ability to create, edit, search, and export client contact details together with internal notes... (Budget: $250 - $1200 AUD, Jobs: Django, HTML, Laravel, MySQL, Node.js, PHP, Software Architecture, Web Application)