Seller did not tell the truth of the building's age

I am buying an apartment building and the seller told me that the building was built in 1986. After I paid $3000.00 for appraisal, I found the building was built in 1978. Is there anybody had this kind experience before? At this moment I am not sure what other information from seller is not true. If I decide not buying this property, can I ask $3000.00 from the seller? If I decide to buy, can I ask the seller to reduce the price? What other options I may have? Thanks in advance for any input, and happy Chinese New Year!