Entry fees? Departure fees? Good lord, everyone needs a piece of you don't they?
I'm really starting to think I should follow you around for a few months!
Again, if you stay in the Caribbean it's quite cheap to clear in a d out of most countries. And it's well known which are the expensive ones! Just look on noonsite.com it has all fees listed.
The Bahamas is the only expensive country at $300 to clear in, but that's for months and its cheap to stay there.
St Martin Dutch side is $25 aprox to clear in and no anchoring fee unless in the lagoon, and there is $20 per week.
French side of St Martin is where local knowledge comes in... Entry 25Euro plus 25 euro per night to anchor! BUT if you clear in at Port Royal, about 300 meter walk away, it's only 7euro and free anchorage!
Antigua is the same... Clear in in English Harbour and pay a National Park fee to anchor, but clear in in Jolly Harbour then it's free to anchor in English Harbour!
So don't worry about clearance fees in the Caribbean.
Remember this whole idea is good for this one area. Don't get the idea it's the same in the Pacific, or the Med.