Just let you issue a credit application format to be signed by buyer with sureties properly verified.
You need insert terms and conditions in the credit application form with conditions of chargining intrest @,,,,,% if payument is delayed beyond...days.
You must let them give you bank details also.
Or simply take psot dated cheques,.,,
OR SIMPLY TRUST ,LET THEM SWEAR THEY PAY YOU...THESE DAYS THE MORAL OF PEOPLE IS TOO THAT THAT THEY ARE BECOMING GOD FEARING LIKE BEING IN SAT YUG....