Budget this trip honestly

When the flights and hotel are booked and you suspect the real number is higher.

Help me build a realistic budget for this trip, including the parts people leave out.

1. Split costs into: fixed and already committed, near-certain daily spend, occasional spend, and the invisible category. The invisible one is what I want most: transfers, bag fees, tips, water, coffees, left luggage, a taxi because it rained, the meal that turned out to be somewhere nice.
2. Give me a daily figure as a range, not a single number, and say what pushes me to each end.
3. Tell me where the money actually goes on a trip of this shape, and which one change would cut the total most.
4. Suggest a contingency percentage and justify it.

Do not quote specific prices for this destination as fact: you will be out of date. Instead give me proportions and structure, and tell me the three things to price-check myself before I set the number.

Destination, dates and travellers:
What is already booked:

Choosing and budgeting. Picking between options, planning around a hard constraint, and what the trip will really cost.