Study each of the following case carefully. Briefly state the principle of law and your decision.

Blackburn, a painting contractor, agreed in writing to paint DeSoto’s house for a certain price. After the house was painted, DeSoto asked Blackburn to paint his garage. Blackburn had other painting jobs scheduled and refused the additional work. DeSoto felt that his offer of additional work was entitled to higher priority. Is DeSoto correct that the completed contract should entitle him to a higher priority?