Build Affordable Multi-Tenant SaaS CRM

I want to develop an affordable, modern, responsive web-based SaaS CRM software for small businesses, agencies, real estate agents, coaching institutes and service providers.

**Main Goal:**
Build a simple CRM platform that helps businesses manage customer leads, track sales and automate follow-up workflows.

**Required Features (MVP):**

1. User registration, login and secure authentication.
2. Modern dashboard with leads, customers and sales statistics.
3. Lead management (add, edit, delete and organize leads).
4. Lead status tracking (New, Contacted, Interested, Converted, Lost).
5. Follow-up reminders and task management.
6. WhatsApp click-to-chat integration with customizable message templates.
7. Customer notes and activity history.
8. Search, filters and CSV export.
9. Responsive design for desktop, tablet and mobile.
10. Multi-user and multi-business support with secure data separation.

**Technical Requirements:**
- Build using a scalable and maintainable technology stack.
- Use affordable hosting and database solutions.
- Avoid unnecessary paid APIs and expensive third-party services.
- Keep the architecture ready for future subscription plans and payment gateway integration.

**Deliverables:**
- Fully functional web application.
- Complete source code.
- Database and backend setup.
- Deployment assistance.
- Basic documentation.
- Ownership of the source code and intellectual property.

**Important:**
I am looking for an experienced freelancer who can suggest the most cost-effective development approach.

Please provide:
1. Your fixed-price quotation.
2. Estimated development timeline.
3. Recommended technology stack.
4. Previous SaaS or CRM projects you have developed.
5. Post-launch bug support.

My priority is a reliable MVP with clean code, good user experience and low development and maintenance costs. I want to develop this product commercially and sell subscriptions to customers.