Senior Full-Stack Dev Team / Agency for AI-Driven Gym OS & Multi-Branch SaaS

We are looking for an elite software development agency or senior dev team to build an enterprise-grade Gym & Sports Complex Operating System from scratch. This is not a basic mobile app. It is a massive, modular, API-first SaaS platform designed to manage multi-branch sports facilities, integrate with IoT hardware, and embed AI at its core. Key System Modules: Core & Security: Multi-branch membership, strict RBAC, secure auth (OTP, QR, Biometrics), and immutable audit logs. Operations & Marketplace: Workflows & bookings for Private Coaching, Group Classes, Cafe/POS, Salon, Massage, Lockers, and Parking. Health & AI: Digital health records, workout/nutrition tracking, AI executive assistants, and AI coaching/analytics. Enterprise & HR: Multi-step hiring, digital employee files, attendance, and dynamic payroll (Base + Commission - Deductions). Hardware & IoT: Integration readiness for smart gates, lockers, HVAC, and AI cameras. Finance & Dashboards: Centralized financial ledger and real-time executive dashboards. Development Roadmap: Phase 1 (MVP): Core system, User management, Auth, RBAC, Basic Membership, and Core Finance. Phases 2-3: Marketplace services, CRM, HR, and Payroll. Phases 4-6: AI integrations, IoT hardware, Multi-Branch scaling, and SaaS readiness. Requirements & Proposal Instructions: Proven experience in building complex enterprise systems, ERPs, or multi-module SaaS platforms. Stack flexibility: Modern backend (Node.js/Python/Go), relational DBs, and scalable frontend (React/Next.js & Flutter/React Native). In your proposal, please include: Links to at least 2 complex enterprise/SaaS systems your team built. Your core team structure (PM, Backend, Frontend, QA). Your proposed tech stack and estimated timeline/budget for Phase 1 (MVP).