This, of course, will depend on the size of the garage you are decluttering. Aaron Cash offers a very useful table of estimates, depending on how big your original, pre-downsizing garage is, and how much clutter you’ve got in it:
Small Garage (1-2 Car): Minimal clutter: A few hours to a day. Moderate clutter: A day to a weekend. Severe clutter: A weekend to a few days.
Medium Garage (2-3 Car): Minimal clutter: A day to a weekend. Moderate clutter: A weekend to a few days. Severe clutter: A few days to a week.
Large Garage (3+ Car or Oversized): Minimal clutter: A weekend to a few days. Moderate clutter: A few days to a week. Severe clutter: A week or more.