Unprofessional behaviour

I requested a quotation from Andre who is a consultant for the Uitenhage branch. The quotation was emailed to me, and I responded to the email to clarify if my understanding is correct in relation to the total cost for the windows so that I can be in a position to process payment accordingly. However what disturbed me was the rude message left by Andre on my voicemail. He was so angry, shouting and annoyed with my query as if I'm stupid for not understanding the spec in the quotation. What he fails to understand is that, as a customer I have to be clear of what's in the quotation before committing to it. I rely on him as a consultant to help me understand the information that's in the quotation, and not shout at me, disrespecting me and yet expect me to do business with Trellidor thereafter. His behaviour was totally unprofessional and as a result i've decided not to engage with him ever again.