Hannah and Jack purchase a home in Boston for $600,000. To finance the purchase, they make a down payment of $100,000 and obtain a purchase money mortgage from Sun Bank. After 5 years, they decide to renovate the kitchen at a cost of $75,000. They apply for and are granted a home equity line of credit from Horizon Bank to pay for the renovation. Three years later, Jack loses his job and he and Hannah default on both loans. The balance due to Sun Bank is $425,000. The balance due to Horizon Bank is $70,000.

The mortgage agreement with Sun Bank includes a power of sale clause. What does this mean?