Construction Services Platform Development -- 2

I'm building a construction services platform in India (starting with equipment rental, expanding later to operators, mechanics, and spare parts). Need someone with n8n Cloud + WhatsApp Business API experience. I have no technical background, so please use n8n's AI Workflow Builder (prompt-based) so I can request future edits in plain language.
What I need:
Set up n8n Cloud account and connect WhatsApp Business API
Integrate payment gateway (Razorpay preferred) to auto-generate UPI/card payment links
Automated lead capture and response for customer inquiries
Auto-generate and send quotation + invoice via WhatsApp on booking, with payment link attached
Real-time payment status tracking (auto-mark "paid" once gateway confirms)
Automated payment reminder every 3-5 days for pending dues
Auto-send terms & conditions with every booking
Structure it so new categories (operators, mechanics, spare parts) can be added later without rebuilding
Please share:
Your experience with n8n Cloud + WhatsApp Business API + Razorpay integration
Whether you can use n8n's AI Workflow Builder for this
Quote for one-time setup + 1 month support
Delivery timeline
Note: Preferred communication language — Hindi (or Marathi). Please mention if you're comfortable communicating in Hindi.