You pick a price. The other guy picks a price. If you're a sucker, you'll let 'em bargain you down to an average of the two prices. Worse, since you named the first, the other guy only had to pick a first price of their own choosing to get you for less than the market rate.
Therefore,
Never meet in the middle. First don't even try to deal until you have MoreThanOneOffer. Use the AbsentProxy to help you stand firm. Explain how you'd really really like to meet them in the middle, but the market just makes that impossible. Then DontHaggleJustWalk. Let 'em chase you until they stop chasing. Then you'll have learned a lot about what they'll really do.
When you begin negotiations there are some things you really care about and some things you don't care about. Ditto for the other party. And neither of you know which issues are which. Negotiation is a learning process where both parties discover what they really care about. If after all the learning is over you have common ground, then you can make a deal. Negotiation has nothing to do with "standing firm".
Oh, don't stand firm. Use this pattern in conjunction with AlterTheOffer, NameTwoFigures and MoreThanOneOffer. Keep things moving. Find the best fit you can find, and then go for it. And remember DontGoToTheHighestBidder.
Part of the NegotiatingPatternLanguage.