Full-Stack Developer for Multi-Tenant SaaS Web App for Building Management & Access Control

I’m looking for an experienced Full-Stack Web Developer to build a Multi-Tenant SaaS Web Application for Access Control Management. I want to develop a platform that is inspired by modern cloud access solutions like Axon Access (https://axon-access.com/) but adapted to transition legacy desktop management systems like Hikvision iVMS-4200 (https://www.hikvision.com/en/support/download/software/ivms4200-series/) into a responsive web environment. The core requirement is a scalable system where multiple independent Building Administrators can create accounts for their residents, manage their own specific buildings, track resident payments, and automatically grant/revoke elevator and door access based on those payments. Core Architecture: Multi-Tenant SaaS - Super Admin Panel: For me to manage the overall SaaS platform, register new building admin accounts, monitor system health, and oversee hardware connection statuses. - Tenant/Building Admin Portal: A private dashboard for each client (building manager) to handle their specific portfolio, add/remove residents, check payment ledgers, and adjust hardware access profiles. Data isolation between tenants must be perfectly secure. Key Features & Requirements - Responsive Web Platform: A modern web-based UI fully optimized for both desktop (laptops) and mobile browsers (smartphones) for administrators on the go. - Hardware Integration (Crucial Requirement): The platform must communicate over the cloud/network with local access control panels. We use 1) ZKTeco C3-100/200/400 series panels and 2) Hikvision DS-K2801 series controllers. You must be comfortable implementing remote commands (open/lock/sync users) using SDKs/APIs or direct TCP/IP socket programming. - Payment & Access Automation: An administration module to log resident fee payments. The system should automatically talk to the hardware to unlock access when a payment is logged and revoke it if a payment expires or is flagged. Note: No payment will be handled in the system for this time. Only a date field with expiration date for each client. - Real-Time System Monitoring: Live status updates of all connected controllers and elevators/doors. - Automated Notifications: Web-app push alerts and emails for critical events (alarms, hardware disconnections, elevator faults). - Role-Based Access Control (RBAC): Tiered permissions within a single tenant account (e.g., Owner, Property Manager, Technician). - Service Control & Maintenance - automatic notifications for service due dates, inspections and certifications. - Logs, Auditing & Analytics: Comprehensive event logs tracking every technical event, card scan, or configuration change, alongside analytics/stats regarding elevator usage and alarm frequencies. Qualifications I'm looking for: - Proven experience building Multi-Tenant SaaS web applications. - Strong background in IoT or Access Control hardware integration (specifically ZKTeco SDK or Hikvision ISAPI/SDK). - Experience implementing real-time data handling How to Apply Please highlight your experience with Multi-Tenant software architectures and hardware integration. Let me know if you have previously worked with ZKTeco or Hikvision devices, and share links or screenshots of admin dashboards you have built.