Bulding management system

I am looking for a freelancer to build a building management system for me. This system needs to have access control as the main feature. The development should be done under a proprietary software, meaning that the source code cannot be shared with third parties.The size of the building or facility that needs to be managed is quite large, with over 50 rooms. I am looking for someone who is experienced in building management system development and is able to deliver quality work.

Person should be available Riyadh, Saudi Arabia