We need a Bespoke Document Management System

General information for the business: Business to Business Consultancy
Kind of development: New program from scratch
Description of requirements/functionality: Hi

Our company is seeking a developer with experience of creating Document Management Software (DMS). We require a bespoke DMS solution with all of the key features of typical off-the-shelf solutions – namely :

Ability to upload & Download Docs (Word & Excel)
Ability to edit documents by approved group users
Version control
Tracking
Messaging

Obviously there are many other potential features and these can be discussed further down the line. The really crucial thing about our DMS requirement is that we want a solution that will allow hundreds of external users (our customers) to access the software. Each user will need a secure password-protected area that can only be accessed by approved users.

We would manage and host the DMS on our own server.

It would be preferred if you have previous experience with Document Management software.
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