My parents inherited large collection of art in 1971, Dad died in 2014. We siblings sold all for $905,000.00 after auction house fees. How do we figure basis in 2014.

[CareyM855]

It's impossible to evaluate as it was over 300 items the only way i could think of was to do reverse inflation calculation as a basis in 2014

[Bsch4477]

Inheritance is not taxed. If you inherited the assets and sold them soon after your dad died the cost basis is the value at the time of his death so there would be nothing to report since there was no gain. 

[CareyM855]

Dad died 2014 we sold art 2024 so trying to figure cost basis in 2014 thanks   I probably wasn't clear on my question

[CareyM855]

Mom is still alive 

[Bsch4477]

My mistake. One question is who owned the assets?  Only the owner or owners can take the deduction. 

If mom owned them only she can take the deduction. If she gifted the assets to her children she has to file a gift tax form 709. As to the cost basis, the basis of gifted assets is the cost basis of the one who gave the gift. If the assets were owned jointly by your parents there would be a step up in cost basis for Dad’s ownership when he died. Given the large amount of money involved as well as the complexity you really should get professional advice.