I thought I might take the time to write about the things that we look for in a boat for living aboard and cruising. Everyone - these are our opinions and please understand that our opinions are heavily biased on the type of cruising we do, our location, and that we have a family.
As everyone knows, we have two kids - 6 & 10 yo. We also have a fat bulldog that we have mutually decided not to eat, yet, and which has decided not to eat us, yet. I have no interest in seeing the poles. And although my boat would cross the Atlantic, it is not high on my list. I think I would probably opt to ship her across via dockwise if I wanted to cross or go with a group via the ARC. We prefer warm weather and pretty water. So our ideal cruising circles are the coasts from S America to N America, with the islands (including Bermuda) inbetween.
On the outside:
First and formost - I like boats that can get out of their own way and are sure footed. This is a deal breaker for us, not a preference. We owned a Catalina 380 before this boat and although she was a VERY solid boat, she was slow. I know many people think that is not a big deal because you have all the time in the world, but I could not dissagree more. Poor performing boats will put you in harms way longer when making a passage in a storm. They are more of a hassle to handle through seas. They are going to add a LOT of time between passages (this is big one with kids). You will use less fuel because you will sail more. You will actually enjoy going out and sailing. It doesn't mean that you need a TP-52... but I would opt for the performance cruiser over the typical cruiser.
I would not buy a boat with a draft over 6 feet. I prefer a fin keel, but most fin's on 40ish feet are too deep, so opt for a wing.
Nice, big cockpit. You will spend a LOT of time here, esp as a family. You will eat here at anchor a lot, do homework here, clean your fish here, and entertain here (actually something we do a LOT of which most boats cannot comfortably do). There is a common beliefe amongst old sailors that large cockpits are a hazard. I do not agree. I have not been in a storm yet where I felt it was a hazard. Handholds are what makes it safe. We also have two wheels which I really like most of the time... just not at docking. If I had to pick between them, I would take a two wheeled boat. It also adds a safety redundancy.
Sugar Scoop (nice swimming transom). THis is not quite a deal killer as there are boats I like that do not have this, but it would be a huge negative. How much? Well, we have seen many boats that have been modified swept backs to accomodate a sugar scoop. WHy is it a big deal? MANY reasons - your dink is your car and boarding from the side with kids and/or a dog is a real hassle... esp in seas. The kids swim off the back all the time and it is an easy place to watch them and for them to board on/off. It is a great place to wash clothes or the dog (or yourself when covered in sand) without tracking it inside. In a MOB situation, it is about the only way my wife could pull me back onto the boat. It also makes a very convenient and easy way to place davits (which I also think are a necessity). Raising the dink with davits on most other stern types is a real hassle (IMHO).
LOTS OF HATCHES for ventilation... believe me! You will want them.
Decent lazarette as you will be hauling scooters, snorkeling gear/dive gear, likely a generator, air conditioner, will be back there, all kinds of extra lines and a gazillion other things that flat out take up a lot of space.
Toe Rail. This is a deal breaker if it does not have one - with my very strong prefernce the aluminum one with holes to add blocks or netting if you want.
Midships cleat(s). I know this sounds silly, but many of the docks we have been at have very short boarding and we like to keep the stern close to the dock for the kids and dogs and a midship really makes this a lot easier.
Large anchor locker. Our anchor locker holds 2-3 anchors (one is the tender anchor when not in use). One anchor is all chain (250') and the other is a combo of 35' chain and line. A windless, manual or electric, is absolutely necessary. We also use this locker to store other anchoring related gear and the washdown sprayer and anchor balls and other misc equipment.
Good rub rail... for obvious reasons.
Roller furling jib. We have an inmast furler and the mroe I have used it, the more I think I would opt for it over a standard Slab reef. It keeps everyone in the cockpit and safe - esp when soloing at night and trying to shake out/in a reef.
Ability to carry at least two propane tanks.
Good spot to mount a grill(s). I nknow many people make fun of me, but we cook a LOT outside on our boat. I blacken fish there (not good to do inside) and many other things that make living on our boat so much more enjoyable. You can get by without a grill, of course... but I find it to be more versatile than the typical grill at home and a lot more fun to use.
If the boat has not raisesd its waterline, plan on it (roughly 3 inches).
Put in doors to downbelow if it does not already have them... but make sure they can be removed and boards dropped in during a storm (that is what we do). But stepping over the boards is impracticle for any long term boating esp with kids.
One electric winch sure is nice when someone has to go up the mast or to raise the tender... but not a deal breaker.
BIG dodger and and bimini. The didger does more than just block the wind. It also is a great place to throw the kids life jackets when they are down below as well as other things that could blow away in the wind. It is like adding another small room... as is an encloseure. We have an enclosure, but only use during winter months. It will give you another room on your boat.
Mast under 65, with 62-63 the top limit preference. This is a deal breaker.
We have two heads and a seperate shower. THough both heads have the ability to shower, only ours is used as it is seperate. This is a deal breaker - not having a seperate enclosed shower. We have done it both ways and having to wipe up after that shower is a real pain in the butt and not very practical for a family where the kids ar elucky to pick up their own towels. If I only had one child, I might prefer one head over two since it gives you a lot more room in the rest of the boat. However, with two kids I would definitely opt for the second head. Be forewarned that a forward head is worthless in a sea or even moderate chop. Instead, see if you can get the second head closer to the mast or aft... if possible.
At least one straight salon settee for laying on during a passage and/or setting up lee cloths. Curved settes are worthless.
Much prefer deck stepped over keel stepped mast.
Deep bilge. This is both so the water runs into it no matter what point of sail, but also because it is a great place for putting can goods, water, wine, beer, and other heavy items that can tolerate geting wet. Ours stays full.
EASY wire runs and plumbing runs.
All around access to the diesel with a strong preference not to have to climb over a a settee to get to it (as is common on many aft cockpit boats and 3 SR boats). Needs to be well sized. Check for Impeller acessibility and ease to service.
Lots of below waterline storage and 'cabinets' where you can mount a/c's, watermaker, breadmaker (ugh), pots and pans, etc.
Comfortable salon where we can all gather around the table to play games, do homework, eat, and watch movies.
Descent (not smaller than 3-6 CF/piece) freezer and fridge. Gimballed stove (propane only... no alcohol). Lot of cabinets for dinnerware and cookware and foodstores. Microwave. Centerline sink. Seperate Nav Station with an abudance of expansion potential... prefer forward facing .
Reasonable water and diesel tankage, with 120-150 water preferred as well as 60-80 gallons diesel prefered. Depending on the boat, these can be reduced some as the better performing boats will use less diesel and watermakers make large water caps not as critical. I would strongly prefer two seperate tanks for water as we use our aft tank when we run out of the fwd and know to be consesrvative from there (better than running out in the shower and not having a drop left!!).
Lots and lots of cabinets for books and games and all the other gazillion things we need to make life comfortable. The Kindle makes some of this less critical (books).
Our very strong preference is a centerline queen where either person can roll out of bed without disturbing the other. Maybe not a deal breaker, but very close. TIght V-berths are hard to make up and one person always distrubs the other. Pullmans means one person has to crawl over the other person at night to pee or check anchor or whatever... and are not as easy to make up. Rememnber, this is your home, not a weekender, and you need to make this comfortable. Others are fine with V's and Pullman's. I am explaining why we are not.
For the kids, seperate berths would strongly be preferred, but this becomes difficult on boats in the 40' range or below. Our kids have been in a V berth most of their lives and even as live aboards do not mind it. But I suspect come puberty, it will become more of an issue. WIll also be more of an issue if not both same sex.
For those boat shopping, I hope you will find this list helpful. Your opinions may be completely different from ours, but at least this gives you some things to consider when looking at the boats. Incidentally, I doubt there is a boat that matches all of these requirements. Our Catalain 400 does not, but it came close. So instead of finding the boat that meets all of your requirements, make your own list on what YOU feel are deal breakers and preferences and see which boats work for you. I also welcome any other sailors to add to this thread with their opinions and why they feel that way as it will help the discussions.