A list of items to consider when planning a trip

A list of things to consider:

1. Destination—that is, city or town I will end up at, and (separately) airport I will fly into. If you're not sure, Sky Scanner offers searching prices by month and by vague destination. For example, "United States (any)," or "New York (any)."
2. Itinerary. Where specifically am I going? John Smith Park. Jane Doe Beach. Sal Placeholder Convention Center. The Examploos Lodge. What are their fees? How far is it from where I might stay? Anything I need to bring for that? If applicable; Can I prepay, and do I need to? Beach fee? Beach sticker? Parking fees?
3. If flying: Air fare. Baggage fees.
4. Lodging.
5. Pet lodging, if needed.
6. Transport. Bus, train, tram tickets. Car rentals and price of gas.
7. Food.
8. Any incidental supplies needed: Travel-size bottles of soap, shampoo, shaving cream, luggage, etc.

I feel like this must be missing something, but I can't name it.