Please find enclosed with this letter a check for two months' payment, plus a late fee. I am sorry for the delay, but I was unable to send last month's payment on time due to unexpected medical expenses. I appreciate the opportunity to do business with you and ask for your understanding during this temporary financial difficulty.
Enclosed is a check for half the amount of rent I owe you. I expect to be able to pay the outstanding balance, including the late fee, on or before the 20th. I am sorry to be so late with my payment, and hope that this has not caused you any great inconvenience. My hours at work were cut unexpectedly, leaving me short of money this week. I am just starting another job and will be able to pay on time in the future.