You know what bothers me? When I get emails from people inquiring if they might be able to buy one of my domains and no offer price is included. And then if I respond yes, I would be willing to sell, when they come back and ask me how much I want for the domain. Hey, if you're contacting me, tell me how much you want to pay! Don't expect me to name a price.
Lately, I've taken to responding to the initial query: yes, I might sell, but will talk to you only if you make an offer with a number. This seems to kill any interest because they never email back.
I suspect that some of these email inquiries are made by flunkies told to go out and find out how much a bunch of domains cost, for presentation to a decision maker who will then decide which ones to buy. Please don't email me if that is how you operate. I am not a domain broker. I have some domains for websites, and I will sell for the right price, but I am not in the business of giving your boss a price for his consideration.
Almost as bad are people who email me about domains they want to sell, but without a price attached. Don't bother.