This is business, and when it comes to business, friendship shouldn't be involved.
Actually, Yang Yi and Justin didn't have much of a friendship to speak of; they had only cooperated once, and then Justin had helped Organization of Water find a training ground, but Yang Yi had paid for it. The favor Justin did by acting as an undercover for Yang Yi in Deyo was already repaid.
So, Yang Yi definitely had to bargain with Justin to secure the greatest benefits for himself. However, with no intelligence at hand, he could only wait until he actually had information to negotiate seriously.
Moreover, you can trust the intelligence from an information broker, as their credibility is essential to their livelihood. But aside from intelligence, you mustn't listen to anything else they say. Befriending an information broker would be irresponsible to your own life, wouldn't it?
