"so the family sold his home and have a gain of 45000"

"primary home... they sold it with in 3 months... to just unload it."

That has established the value, then. There is no gain and no need for an assessment or appraisal. Assessor rates are typically under market. Appraisals to establish FMV are moot, as long as it wasn't sold at some huge discount to a family member. If it was sold on the open market, that's its value by definition and that's why there is no concern as to original basis, improvements, gain or loss. The only expenses were the sale costs. There is no taxable gain for anyone to split.