Decide how many individuals/couples will be going as this determines the size vessel/ layout. With 1 couple per stateroom, the size cat will be fine. Do not try to use the salon as a sleeping area and generally single berths are best for captain/ crew, and sometimes okay for kids. Do NOT overcrowd. Most are well suited for 4 couples with more than 4 couples requiring even larger yachts. Get real commitment from those going as a late dropout can be costly to the others who pay to go.
Most cats over 40 feet will have generator and air conditioners, which I will argue will be very important for at least some of your group.
Determine if you (and some of the others) want to be guests on a boat or if your intent is to learn some/a lot about sailing. If you really want to learn, chartering a bareboat with ASA instructional skipper may be best. If you want to be served and no hands on sailing, then a crewed boat (Captain and first mate(who likely will serve as cook, maid, and deckhand)) may be perfect for you.
Plan a general cruising itinerary and expect it to change . Let captain know if you want more partying or more secluded anchorages. Let him know if you want more time under sail or more time snorkeling , exploring, etc.
Many great companies out there. Almost all of the charter boats are owned by individuals and managed the companies. Chartering directly from owners is also an option as inferred by Kryssa. Many of the sponsors are individual owners (like me) as my new Lagoon 42 is Sea Tiger (www BareboatBVI).
