Hi Wren,
I don't profess to be a professional domain name seller although I do aspire to be utterly professional in all my dealings with everyone.
I am slowly increasing my end user sales which is probably coming from sending out more emails rather than having any magic formula for negotiating a deal. A poor negotiating ability carried out many times is I think rather better than an excellent one carried out only once or twice. And the more I do it, hopefully the better I will become.
Whatever you are sending out to the other party - would you be happy to be on the receiving end of that treatment from someone else?
If they start asking loads of questions, take that as a good sign that they are interested - the ones that ask no questions are probably not going to buy.
Check the NP name evaluator to get some idea of worth. Be realistic with the market rating for the name you are checking.
I usually ask the other party to tell me what they think the name is worth to them - in my experience in more cases than not they will come back with a realistic answer rather than a derisory $10 - $50 reply. And occasionally the figure that comes back is higher than I expect!
I am usually loathe to accept the first offer, even if it is acceptable for me. This is because people love to haggle and if this happens, both sides can come away from the deal thinking they have won - you as seller will probably have made a good profit and the buyer has got the name for less than you were originally asking. If you accept the first offer, the buyer wonders if he could have got the name for even less and does not have the same sense of satisfaction that can come after even a small amount of haggling.
How do you tell if you are selling yourself short - very difficult. A name is only worth what someone is willing to pay for it. A buyer may come along, eventually, at a high price but my philosophy is to get the sales now, have a win-win situation by not asking top dollar, and if I lose out by selling $100 lower than the maximum possible, I gain by getting more of those lower sales.
My names will never sell for vast prices but I am quite happy turning a registration fee into $200-500. And there are so many good names out there not currently registered that it is not too difficult to find names that are marketable, especially if you choose a niche industry to work in.
Hope this rambling helps a little.
Best regards
DavidH