Your customer renders late money, appears having lame excuses and you will pleads forgiveness, so that you usually do not strike him which have a late payment. Just after performing this for some days, you get fed up with they and decide to fees late costs and maybe even foreclose. He today spends your a beneficial character against you since the a coverage to not pay the late fee or even allege your are unable to foreclose since you approved later payments prior to now (waiver and you may estoppel–they are able to work as defenses for very long waits).