New Roof Installation Sharks in Centurion !!!!!!!!!!

My Braai Area Roof: What turned out as a lovely experience after the summer holidays went fine with the payment and ordering of the material to the value of R30 000. When it came to roof installation they demanded that the R5000 installation fee be paid upfront, leaving me no quality assurance on the installation. The management would not budge... I am used to receiving any service and perform EFT payment before leaving site and after inspecting. Roof Source sucks !!!!