Shady pricing issues and refusal to honour telephonic quote by owner

Shawn(presumably the owner) quoted me telephonically R15k-R16k for a Bambulab P1S and R499 for a hardened steel nozel. I got to the store and Paid R17k and R850 respectively. I thought it is due to the Rand fluctuations in SA but I found out from an employee that the get there Bambulab stock from Rapid 3D. Rapid sells the products for exactly what EC3D quoted me for bit they still added almost a couple of thousand Rands on top of that in-spite of quoting me a lesser amount over the phone. I called Shawn to let him know what I found out and he got snarky saying well I quoted this but I charged that because we are not a charity. This is business and we have overhead charges. I said thats fine but quote a client with those things in mind.