This seems to be a unusual personality trait and I don’t understand why. I won’t allow myself to be sold anything whatsoever by any type of salesperson whether it is an extended warranty, a timeshare, or an additional service for something that I buy. The default answer is always a hard no to everything unless I get some overwhelming evidence that might be something I should look into later. The best that they can do is provide good information for me to go back home and research.
I just hang up if it is a cold call or warn them that they better cease and desist immediately if it is something that I want to buy in person. I have and will just walk out if it continues without any guilt or pretense. I think that is perfectly logical but there are painfully to few people that do that and those that do play along support predatory and unethical businesses.
What seems to be a little more unusual is that I refuse to negotiate on just about anything to do with money. When I buy a car, I do lots of research and then I just walk in and make a take it or leave it offer. They usually take it but sometimes they don’t and that is perfectly within their rights and I will find another dealer. That is the end of it and it is not a game. The same thing applies to houses or anything else I might buy.
What is the point of negotiating about anything remotely like that? You set your price based on the best information you have available and I don’t see why anything or anyone should modify that position unless it reduces the price?
I have haggled in places where most would never think you could haggle. Now, you do have to be realistic. But still, I have got a %= sales tax by paying cash, a discount = to delivery charge from a place that offered “free delivery”, a “case” discount, and a shopworn shelf-sample discount (40%!). And those not at flea markets, either- those were at retail chains. But make sure you have a legit reason (like those I offered) to offer less. “Paying cash” usually won’t work except at a sole prop., of course.