Over charged fo number plates

It is with deep regret that I write this article on the promise to do redo two sets of number plates that were wrongly done last year. I was Introduced to Exclusive Number Plates by a worker at East Coast Panel BEATERS named Wiseman. Our request was for a set of the new number plates for two vehicles. The owner made two set of plates but they were not the new plates. It was the same original plates. He charged me R600. After a lot of back and fourth he promised to do the new number plater the next year for R500. I went there today and the owner charged me R350 plus R30 for tape. For one vehicle. He refused to reduce the rate to what he promised me. How does one ever do business with with a company that does not keep to their word