Ethical boundaries to working with a "bird dog"

[Dori Arazi]

I've been working with a bird-do out of state. He send me multiple deals a day, not all terribly bad, but none of them are gems by any means. 

He obviously gets paid when we execute, and he's been exhibiting frustration that none of the deals have been selected. Backed by the concept that no deal is perfect and that I'll be bale to find something wrong with any deal he sends ( we've been hunting for deals for only a few days). 

We do have some pretty strongly defined parameters as to what would be considered a good deal.  While not common, I don't think these deals are rare. 

What are the ethical limitations here? How do you balance what seems to be a conflict of interest?