Dial a gate Marius Van Der Merwe stole almost R7000 From my 77 year old mother

Dial a gate - Marius Van Der Merwe from Sunward Park boksburg. Came out in April and gave my mom a 77 year old pensioner a quote for security gates. She paid him a deposit of almost R7000. He has made excuses and we eventually said he must pay her money back. He avoids us and has been aggressive when we have spoken to him. He drives a white Ford ranger and has shoulder length brown hair. He comes across as being very friendly. Late 40's. I looked up reviews tonight and found that he has done the same to other people as on hello Peter. If anyone has any information please message me. Not sure what to do anymore as we have now been blocked. And his website www.dialagate.co.za no longer exists. The cell numbers we have are *** and ***. Is there anyone whom could offer some assistance in order to trace these numbers or Marius