How much cash should I take?

One question I get a lot from clients is "How much cash should I take?"
In general, I like to prepay for as much as possible to minimize the amount of cash I need to bring.
Here's how I figure how much cash to bring:
1. Tips for drivers and guides - I make list of all my transfers and excursions and how much I'd like to tip.
2. Shopping and meals - Will we be places where we will need cash to shop or buy a meal?
3. Tips for housekeeping, waiters, and bartenders - I make a list of tips I'll want to leave for the staff. For all-inclusive resorts and cruises, we budget $10 - $15 a day since gratuities are included or charged to our on board account.
4. Transportation - Will I need to take a taxi? I google how much that will cost.
5. The emergency $100 - I always have $100 in emergency cash.
6. Casino Cash - Is there a casino? How much do I want to gamble?

On cruises, I make an envelope for each port with the amount of cash I'll need for that port.