Build a Centralized Custom WhatsApp Chatbot System (PHP/MySQL) + Server Setup & Maintenance Contract

Project Description Overview: We are looking for an expert developer to build a comprehensive, automated WhatsApp Chatbot system for our commercial group and its various subsidiaries/applications. This will serve as a centralized, smart contact point to handle inquiries from clients, advertisers, and partners, routing them dynamically based on the specific project or department they need. Core Technical Requirements: Backend & Database: The core system and the admin dashboard must be built using PHP and MySQL. WhatsApp Integration: We require the use of unofficial WhatsApp libraries (e.g., WhatsApp Web.js, Baileys, or similar QR-code-based integrations) linked to the PHP environment. We DO NOT want to use the official Meta Cloud API. Our goal is to bypass Meta’s template restrictions and per-message pricing to ensure complete freedom of use for our group. Dynamic Routing (Centralized Bot): Development of an interactive, database-driven response tree (Interactive Menus/Keywords) covering all our services. The system should allow users to: Select the specific project/app they are inquiring about from a main menu. Navigate branched menus specific to each project (e.g., Technical Support, Ad Space Rentals, Coupons, Sales, etc.). Forward special requests or route VIP clients directly to the relevant administrative department within the group. Comprehensive Admin Dashboard: A robust PHP-based control panel giving management absolute control over the system. Features must include: adding/editing/deleting projects, customizing the response tree for each project dynamically, and monitoring chat logs and incoming requests. Infrastructure & Hosting: In your proposal, you must recommend the best hosting environment/server (VPS/Cloud) capable of handling 24/7 uptime and managing the traffic of a multi-project corporate system. You will be responsible for server setup, environment configuration, and full deployment of the system. Contract & Maintenance Terms (CRITICAL): Source Code: Full ownership of the Source Code must be handed over upon completion. It will remain our exclusive property. Maintenance Contract: Your bid MUST include a clear plan and cost for a periodic maintenance and modification contract (monthly or annually). We understand that unofficial WhatsApp libraries require updates to keep up with WhatsApp's underlying changes. We are looking for a long-term technical partner who guarantees system stability and immediate updates when necessary. Required Skills: Advanced expertise in PHP and MySQL. Proven experience in building APIs and integrating unofficial WhatsApp libraries within a PHP environment. Strong understanding of database design for multi-tenant/multi-project architectures. Solid Server Administration and deployment skills. When applying, please provide: The specific method/library you propose for integrating WhatsApp with PHP. Your recommended server/VPS setup and its estimated cost. The details and cost of your post-delivery maintenance and technical support contract.