Where a broker agrees to sell land upon condition that the owner shall first make $500 out of the sale, the broker to have the rest of the profit as his commissions, he is not entitled to the commission for merely finding a purchaser, upon a sale to such purchaser falling through on account of a defect in the title. Seattle Land Co. v. Day, 2 Wash. 27 P. 74. Compare 'Druker v. Gunn, 41 Kan. 496, 21 P. 637. See also Sec. 630.