Based on my experience and observations, replacing or repairing Face ID functionality on Apple devices can sometimes be costly, with prices around $100 being fairly typical depending on the service provider and the extent of the repair needed. Face ID is a sophisticated facial recognition system that relies on multiple sensors and components. When these parts malfunction, it's not always a straightforward fix. Many users might hesitate to pay for repairs, but maintaining Face ID security is crucial for protecting personal information. It's important to seek reputable repair shops or authorized service centers to ensure quality service and avoid further damage. Additionally, some users have found that purchasing a device protection plan beforehand can help mitigate these unexpected fees. When considering repair options, always compare quotes from different service providers. Sometimes, price differences reflect varying levels of service quality and part authenticity. Also, keep in mind that unofficial repairs might void warranties or reduce device performance. In summary, while the $100 cost for Face ID repair might initially seem high, it is an investment in security and device functionality that can prevent more significant complications down the line. Always research and choose services wisely to balance cost and quality effectively.