[Icelander]

The PCs live and work on a superyacht, the Penemue, owned by an eccentric billionaire. It was designed in the 1960s to be a toy for a macho adventurer and, at the time it was built, was not record breaking in size or decadent luxury, but was reasonably near the top-of-the-line for performance in traditional yacht designs of the time.

A major design goal was a fast cruising speed, but, curiously, with enough space for the owner to live there year round, with a fairly decent household. It's built so he'll enjoy living there and lack no essential comforts, but it is meant to vow rich enthusiasts of manly sports, powerful engines and macho aesthetic, not decadent sybarites looking to see how much conspicuous consumption can fit into a hull.

Let's imagine that the prospective owner was proud of having become rich through various cutthroat adventures and that he wanted the riverboat gamblers, gangsters, smugglers, colonial adventurers, big game hunters, mercenaries, mining engineers and mineral prospectors that he still considered as an ideal of manhood to admire his yacht. So it's a very powerful machine and a feat of engineering, always keeping in mind, however, that it is cutting-edge for the 1960s, but that modern designs can, obviously, blow it out of the water.

Exact dimensions as yet not quite nailed down, but over 150' long. Large enough to afford lots of space for the needed facilities and people, as well as having cruising speed and endurance almost comparable to powerful Coast Guard cutters, plenty of seaworthiness and the ability to sail the Caribbean in any weather.

Not so large that she can't enter many harbours on the Gulf Coast or can only berth in extremely unusual marinas, ideally not too large so that she can't sail up the Lower Mississippi in a pinch, at least until Memphis or so.

Can anyone help me narrow down the size range I want?

She must be able to carry up to forty people without double bunking or creating resentment, though that will probably not be her standard complement for much of the year. If she were a naval vessel, she'd carry about 10-12 ratings, eight personnel who rate as CPOs or the kind of civilian experts who need marginally more attention paid to their social status than the ratings and about the same number who rate as 'officers', though this includes such non-military people as a librarian and executive secretary.

Total crew 25-30, which includes an away team, though she ought to be easily handled by less than ten people under ordinary circumstances.

As for space for guests, I'd want want six large living cabins, ideally in addition to the master chamber where the owner lives. I want a library, an armoury, a machine workshop and a very odd room that's about the size of a kitchen, but is in addition to any facilities needed to feed and entertain everyone aboard.

The ability to carry a decent motorboat as a tender would be nice, support for a helicopter and sea plane would be nice, but completely unrealistic goals. In any case, she was built in the late 1960s and while there's been plenty of money for maintenance and furnishings, the owner has had no interest in putting more modern electronics in it than are absolutely necessary.

What kind of size am I looking for and how big can I go without sacrificing the ability to visit lots of Caribbean and Gulf Coast harbours and moor the yacht at numerous marinas, not just a few that are among the largest in the world?