How am I perfectly prepared for the trip (checklist)?

A checklist for perfect travel planning, what do you have to keep in mind, apart from the list of participants:

TRAVEL PREPARATION

• Report or reduce group size and number of participants in good time (to avoid cancellation costs)
• Entry requirements
• ID documents (valid for 6 months after return) and (E) visa
• Health regulations and vaccinations
• Language
• Currency
• Voltage / Adapter
• Customs regulation
• Additional insurance (travel risk, sickness abroad, travel cancellation)

FLIGHT

• Booking confirmation with e-ticket number (flight number, time and route)
• Luggage limit (hand luggage & free luggage) in kg and cm
• Carry-on baggage regulations (liquids, dangerous and prohibited items)
• Registering additional / bulky baggage
• Sign up for special food
• Registration of special service (wheelchair, Little Red Riding Hood)
• Booking seats
• Getting to the airport (Rail & Fly, Park & Fly, overnight stay)
• Meeting point (place and time) at the airport - When and where is the best time to arrange the meeting point at the airport?
• Check-in options
• Check-in counter including terminal (evening check-in if necessary)

HOTEL

• Adress
• Holding and parking facilities
• Shuttle Bus (Airport / Downtown)
• Check-In / Check-Out times
• Quick or group check in (pre-fill registration form)
• Accounting
• Room type (separate beds or 2 duvets per room)
• Notification of allergies and food intolerances