What details about travel services must be documented?

The correct answer is focused on essential documentation that ensures clarity and accountability in travel services. For travel agents and service providers, it's crucial to document information such as the booking date, service description, and traveler names.

Documenting the booking date helps establish a timeline for the transactions and the validity of any agreements or offers. The service description provides details about what the traveler can expect, including accommodation, transportation, and any included activities or amenities. Documenting traveler names is vital for accountability and ensures that the correct services are associated with the right individuals, safeguarding against any potential misunderstandings or errors.

The other options fail to encompass the necessary and comprehensive elements required for proper documentation in the travel industry. For example, simply recording the cost of services lacks the contextual information that would help in managing bookings and providing customer service. Recording personal opinions is subjective and not pertinent to the formal requirements of travel documentation. Lastly, focusing only on the availability of leisure activities does not represent the full scope of necessary information required to provide thorough service to travelers.