Bad customer service at City car sound & security Pretoria

What a bad customer service experience. I went in to fit a sound system into my car, had everything with me, was offered a woofer (R950) in a smaller box to save space in the NP200 and i took it. The job was done, i left when they were closing that saturday. The smaller woofer played a lousy sound and i opted to install my old woofer that same saturday. Went back on a monday to return the woofer in exchange for a smash and grab fitment (R850) without any change (R100) back. Was not given an invoice, there is no return policy anywhere on the premises, was told that it is used and they can only give me a value back of R300 on the woofer. I asked of the return policy, and he kept saying No refund and that they are a small business, that was irrelevant, i was not requesting a refund, was only exchanging the woofer for the smash and grab. At city car sound they have lost a customer and i urge all potential customers to go seek fitment centres with clear return policies and good customer service.