Maybe it would be helpful if you describe what makes a "good spot", to you. Some marinas are really nice with all of the amenities, but the people are insufferable. Some are busy with people coming and going all day - others are quiet with rarely a person in sight. Some cater more to
commercial fishing boats and the like, others strictly cater to recreational boaters.
How much do you plan to do on board and how much do you plan to go ashore for? Will you
shower on board?
Laundry? I know some liveaboards that don't even cook on board, and instead eat out for every meal.
What kind of sailing do you like to do? (By the way, if the plan is to simply live on the boat and never really sail it ... I just wouldn't recommend it. There are several people at my marina that live aboard and their boat hasn't moved in years. I guess it is technically cheaper than an apartment, but it tends to make you unpopular - at least around here people look down on that.
To me, the best arrangement is to have a slip that you can sublet. Then, you have some place to stay during the off-season, but then you can sublet during
boating season when moorage is in high demand and you will want to sail about anyway.
Another good arrangement is to find someone with a private or
commercial dock that is underutilized. Every now and then, you will find someone who is happy to make a few bucks on that unused capacity, and also to have someone on site outside of business hours. Generally, these aren't glamorous locations, but can sometimes be made quite comfortable and tend to be quiter at night than a marina.
Also, is it important to live in a warm climate? Do you prefer the
east coast or the good coast? Are you firm on staying in the US?
It's entire possible, and completely valid, to not have the answers to many of these questions. But, if you don't know yet, then I would take the
advice above and avoid tying yourself down to one spot, but instead to take advantage of your freedom. You might end up some place that you decide to stay, you might not.
Enjoy the ride. It's pretty good.