The worst thing you can possibly do in a deal is seem desperate to make it. That makes the other guy smell blood, and then you're dead. The best thing you can do is deal from strength, and leverage is the biggest strength you can have. Leverage is having something the other guy wants. Or better yet, needs. Or best of all, simply can't do without. Unfortunately, that isn't always the case, which is why leverage often requires imagination, and salesmanship.