If this is the year you are downsizing to a smaller home, the most important streamlining job you can do in the run up to the move is to declutter. Doing so will mean you can not just arrive organized, but arrive with a plan for where your belongings will go, and arrive with the items, from your favorite home decor finds to paperwork, that you simply can't live without.
Decluttering your home isn't a done-in-one-go job; it's a progression. But unlike when you're just decluttering to make your home tidier, doing so to downsize will force you to be more ruthless. The upside? Your new, smaller home will be so much more curated as a result.
