Something I picked up on elsewhere on here for the above scenario is setting up a quick website hinting that your becoming a competitor of the business your trying to sell a domain to.
Then email their MD asking if they would be willing to sell THEIR domain to you, because your entering the market blah blah.
In some cases it seems they see you as a competitor and will buy your name from you just because it is in their companies interest.
I havent tried this but will be.
Obviously you cant do this straight after a sales pitch as they will figure it out.