I have put a sale through at the start of September. Client agreed to seven day payment as we stumped the cash up front for him. He the informed me the check would be in the post. Never emerged, resent again apparently and informed me that the check would be resent never emerged. Never had the check then the bank transfer went wrong so passed to debit collection who then informed his terms are 30 days. What do you do about clients that try to dictate their payment terms to you and change the payment terms to suit themselves. Apart from not allowing him to use us again.