When I plan a vacation I pick my dates, then my hotel, then my ADRs.
Everything else moves around those points. Now, honestly, on the past few vacations I've been moving around and changing my ADRs right up until the weeks ahead of my trip. That tends to toss the whole plan in the air an freak me out, but I'm trying to learn how to be more flexible this year.
In what order do you plan? Do you have fixed points, or are you flexible? Is there a point in time that you say that's it and make no more changes?