Negotiating a sale will likely get frustrating, so you'll need to keep your cool no matter what may happen.
Below is a list of the most agreed upon skills needed for quality negotiation:
1. Planning skills
2. Ability to think clearly under stress
3. General practical intelligence
4. Verbal ability
5. Product knowledge
6. Personal integrity
7. Ability to perceive and exploit power
Once you've figured out where to go for your training, make sure they are giving value for dollar. There are a lot organizations out there charging huge bucks and not giving the greatest guarantees, or giving the most effective training.