A dealer must notify which entity if local authorities require changes to the electrical or mechanical systems of a mobilehome?

The correct answer is to notify the Department of Housing and Community Development (HCD). This agency is responsible for overseeing mobilehome and manufactured housing regulations in California. When local authorities mandate changes to the electrical or mechanical systems of a mobilehome, it is crucial for the dealer to inform the HCD so that they can ensure compliance with state standards and regulations. This notification helps maintain safety and structural integrity while ensuring that the mobilehome meets all necessary codes.

Engaging with the HCD is particularly important because the department has the authority to enforce building codes specific to mobilehomes, and they can provide guidance and oversight on required changes. This approach ensures that any alterations made in response to local authority directives are compliant with both local and state regulations, thereby protecting the dealer from potential liabilities and ensuring the safety of homeowners.