1. Technician qualification and experience: Technicians in 800 yuan may have higher skill level and more experience, and can provide more professional and better service.
2. Different services: Technicians in 800 yuan may provide more advanced and complicated services, while technicians in 400 yuan may provide some basic services.
3. Different service environment: Technicians in 800 yuan may provide services in high-end places with more comfortable and elegant environment, while technicians in 400 yuan may provide services in some humble places. Length of service: Technicians in 800 yuan may provide long service, while technicians in 400 yuan may provide short service.