If the broker employed to sell or exchange property understates to the principal the best price or arrangement obtainable, the principal is entitled to recover from him the difference between that obtained and that which might have been obtained. Holmes v. Cathcart, 88 Minn. 213, 92 N. W. 956, 60 L. R. A. 734; Baldwin v. Lewis H. May Co., I11 N. Y. Sup. 121. See also Secs. 290, 412.