Nope. She would pay ZERO taxes on capital gains up to $500,000, under current law. And this is a cap gain. So only $200,000 would be taxable. Also, since eminent domain is being used, she could negotiate a tax abatement from the State for the additional amount. She might still pay Federal on the $200,000, but she would net approx. $600,000 (or more) for a $400,000 home. Not bad. And if it were me, I would get a good attorney and negotiate a larger payment, say $800,000.