I wrote this and then skimmed through the earlier answers, so some of this is repetition.
I'm assuming that this is a grown dog and not a puppy. You're wise to teach him about going outside. Some of our dogs have barked the request, and some haven't. I've known people who put a bell at dog-nose level by their back door and teach the dog to make it ring when there's a need. Otherwise, have him go out first thing in the morning, after every meal, and just before bedtime; let him out other times if he so desires.
At my house we use crates at night and when I'm out of the house, but we're required to crate-train our pups (we raise puppies for Canine Companions for Independence). I bought the biggest size one I could find so Miss Pup can be really comfortable in it. If you don't want to have a crate, get him a big cushy dog bed (or a huge comforter from the thrift store) and teach him that that's his resting place. Consider having one in your bedroom and one in your living room or family room, since he'll want to be with his leaders (you). He may eye your bed with interest; it's up to you to give him a place he'll like just as well. Treats help. And toys - things that are safe for him to chew on.
As far as leaving him indoors when nobody's at home, try it in small doses first. Give him something to chew on and leave the house for five minutes. When you come back, greet him but don't make a big deal; act as if this is an everyday, normal thing. Look for symptoms of separation anxiety (chewing on illegal items, bathroom mistakes). You'll need to work on any anxiety, IF he has any; many dogs don't. Eventually you can leave him alone indoors for longer periods.
Non-crated dogs will sometimes get up at night and wander; you won't need to worry about that too much once you and he are in a routine.
The pet store web sites have gates for big doorways, if you need to think about doing that.
You want to make sure there is no food on the counter at night if he's a counter-surfer. You also want to teach him that the sofa is not his, unless you and your husband actually want to share the sofa with him. Dogs are sensible and love comfort just as people do.
It sounds as if your husband is used to working with dogs. Now it might be a good idea for you and your fur baby to take some obedience classes together. That way your four-footed child will learn to listen to you, and you'll understand him better.