Custom CMS for Auto Detailing Business

I'm looking for a skilled developer to create a custom CMS for my auto detailing company, moving away from my current WordPress site. You can view my existing site at https://cantay-detailing.ch and download the current HTML files at cantay-detailing.ch/deneme/www.zip for reference. The new CMS should be robust, efficient, and tailored to the specific needs of my business.

Key Requirements:
- Develop a custom CMS with a user-friendly backend
- Implement invoicing, financial management, and scheduling features
- Include customer, services, packages, and appointment management
- Integrate an API for car details (Type, Make, Model, Year)
- Frontend features: price calculator, book an appointment, service and package listings
- Additional features: WhatsApp integration, newsletter, mailing, and company data management
- Contact options for inquiries and offers
- Pricing information for business customers

Ideal Skills and Experience:
- Strong experience in developing custom CMS solutions
- Proficiency in backend and frontend development
- Familiarity with API integration and management systems
- Ability to create responsive and user-friendly interfaces
- Excellent communication skills to understand and implement specific business requirements

I'm eager to see how you can help transform my website into a more efficient and comprehensive platform for my auto detailing business.