Thanks for all the answers.
Money is not much of an issue here, aircraft might be registered under a company/ family business umbrella or sorts, accountant still looking into the possibilities. Stated has been that it is easiest to register the aircraft in the continent where there is to be flown the most, the US or Europe. But for say South America and Africa or Asia, generally what registration would work the best, an American or European registration? Anyone any experience flying privates/ business in these continents with aircraft under different registrations?
If the trip might involve multiple legs, for refueling en route one may only do that at an airport that has customs, even if no one disembarks? And can/ do authorities give more hassle to privately owned jets versus owned by a business, anyone experience on this worldwide Latin America. Africa, Asia?
Does anyone have experience when having to do more than 1 leg to get to a destination? Maxing out the range and flight time of the crew? I gather it's customs, everyone taking a hotel and departing the next day again. Any tips or trics?