AI-Driven Document Automation Setup

I’m ready to streamline my small office, starting with document management. The priority is a system that can automatically file every incoming document, allow my team to edit or collaborate on those files in real time, and then archive them for fast, reliable retrieval later... (Budget: £2 - £5 GBP, Jobs: .NET, AI (Artificial Intelligence) HW/SW, AI Automation, AI Content Creation, AI Integration, C# Programming, Sharepoint, Software Architecture)