Legal Question in Real Estate Law in California

I have never heard that "previous owner was a smoker" is a required disclosure. The smell from tobacco use should be detectable upon entry and inspection of a for-sale property. I think the solution is to have the carpets shampooed and the walls and ceiling washed. You could try asking the seller to pay for it, but I don't think there is any legal requirement either for disclosure of smoking nor to pay for clean-up.