(1) Nonpayment of principal, interest and other sums agreed to be paid under the terms of an obligation secured by a mortgage, deed of trust or other instrument constituting a lien or charge on real or personal property; or
(2) Nonpayment of rent and other sums agreed to be paid under the terms of a written lease for the possession, use or occupancy of real property, such insurance also being referred to in the Insurance Code as "lease insurance." [1967 c.359 §39; 1969 c.692 §1]