As long as the property belongs to your parents, only your parents could claim a tax deduction. Your parents could give you the items, then you could claim a deduction, but see below for important rules.
You can’t claim a tax deduction for a donation of a single item or “group of similar items” with a value of more than $5000, unless you have a signed appraisal from a qualified appraiser and you have the signature of a financially responsible official from the charity. In the case of a large household, it might be easier to have an estate sale, and then donate the cash.
Additonally, when donating items of tangible personal property, the value of the tax deduction is limited to the cost basis in the item, unless the charity will use it for an official purpose of the charity, other than fundraising. The cost basis of an item is what the original purchaser paid. In the case of a gift, the cost basis is the price paid by the original owner. For example, this means that if you have an antique piece of furniture that has a market value of $1000, but was purchased 70 years ago by your mother for $100, if you donate it to a charity that will sell it to raise funds, the maximum tax deduction is $100. If you donated it to a museum that was going to keep the item as a piece of antique furniture for exhibit, then you could deduct the fair market value. Another example would be rare books. If you donated rare books to a library, that was going to add them to their collection, you could deduct the fair market value. But if you donated the books to the library in the library was going to sell them to raise money, you can only deduct the price that the original owner paid.
