I’m not annoyed until they insist that I sell them the car for a song. I tell them I’m not interested, and they act like I know nothing. That’s when I get insulted and walk away. If they handle it differently, I’m OK. It’s all in the delivery.
And YOUR mother scrapes bat dung off cave walls! 
I never get insulted when buying or selling a vehicle. It’s strictly business and the only reason to get offended is if someone pushes the issue beyond politeness.
A guy called me one night about 9 o’clock (didn’t know the guy who was calling me from Oklahoma CIty) who stated he heard that I wanting to sell one of my antique Harleys (a panhead). Not true and no idea wbo told the guy this.
I politely declined any discussion of selling anything several times until he offered me 500 bucks. What a farce. Those bikes bring 8500 dollars as a basket case.
He then proceeded to tell me he could buy them “all day long for 500 bucks” at which point I told him to buy all of them he could find and give me a call because I would double his money on every one of them. Followed by my slamming the phone down.
Yeah, I’ve run across a few of those nutcases over the years. Always funny to hear someone tell you they can buy such and such “all day long” for their $X offer price. OhhhKayyy, you really don’t need my widget for $X then, do you? Good luck to ya… I like your response and will steal it for the next opportunity!
But that isn’t what I’d consider insulting- more like aggravating to me.
I’ll never forget a call my Dad fielded many years ago when I was a kid. Financial guy calls about investments, my Dad declines and this guys says “First time I heard of someone who didn’t want to make more money”. My Dad says “If you’re so damn good at making money, what are you calling me for?”. Followed by the phone being assertively replaced in the cradle…