I know many people loathe the idea of a storage facility, but I actually rented a small one while I was decluttering. I would take items there that I wasn't sure I really wanted to give away or sale. It's amazing how much your attachment to an item goes away after it sits unused for six months in storage.
My house was stuffed with extra furniture that was given to me from my grandmother's estate. I actually liked most of it, as long it was spread among my more modern pieces, but I ended up getting rid of about 90% of it in the end.
The other benefit to the storage unit for me was instant gratification. I could see how my house would look without the extra items. If I liked it great, if I wanted the item back I could go grab it.
I had to force myself to actually go down there every few months, instead of just ignoring it and continuing to pay the rental fee. I actually scheduled a time each month, usually the day the rent was due. That way I could go to the office, pay the rent in person, and then go through things.