Cheney (P) entered into a contract to sell real property to Jemmett (D). The purchase price was $32,500 with $5,000 being paid by the first of March, 1977 and the balance of $27,500 plus interest at 9.5% per annum to be paid through an escrow at Treasure Valley Bank. The principal balance had been reduced to $22,745.67 at the time of trial. The agreement stated that no assignment was valid unless the written agreement of P was obtained. D wanted to sell the real estate, and P's consent was solicited. P refused to consent on the proposed assignment. To get around the assignment, a rental and sales agreement was entered into between D and their buyer. The consummation of that transaction was held up by an encumbrance on the property, and the buyer contracted P about that encumbrance and consented to deliver a satisfaction of the encumbrance to the parties. In March 1981, and again in May 5, 1981, P sent D written notice of default based on the alleged assignment/sale/rental agreement for the property. P sued D to compel payment of the full remaining principal balance. The trial court ruled for D and P appealed.