One way to see the results of all of the times you procrastinated about spring cleaning is to begin the process of moving. When you start removing things from cabinets and closets to pack them for the move you may find yourself wondering, "Is all of this stuff really mine?"
Actually, it may be that some of the things you find in the back of the closets or in the basement and garage have been stored there for so long you had forgotten about them. That is a clue that lets you know those items probably do not need to move with you to your new destination.
There's a couple of ways to deal with all of the stuff that you have accumulated over a period of time. You could have a yard sale to reduce the amount of stuff you have to deal with. You could pack up the items you don't need or want and donate them to a local charity.
You may come across things that don't fit nicely into the categories of sell, donate or throw away. They may be sentimental items that you aren't ready to part with, collectibles that got packed away due to a lack of space or things you think you might need and wouldn't want to have to buy again.
A solution to that situation is to rent a storage unit to put those items in. That way you can concentrate on the immediate project of moving and deal with the other stuff later. Consider that solution as acceptable procrastination. Once you are settled into your new place you will be able to decide whether to keep, sell or continue to store all of the items you considered questionable.
If you are moving a considerable distance from your current home, you will want to arrange to store those questionable items in a self storage facility near your new home or have a portable storage container delivered to your new property. That way it will be convenient for you to sort through the items in your free time.