What payment should I request for being a bird dog?

[Rob Greenawalt]

I am currently searching for properties that meet the criteria of my investment "partner". I find and analyze properties and send a detailed analysis to the investor if I think it may be of interest to them. That could be the extent of my work or, it is possible, that in the future I may be called upon to actually visit a property as well. 

My question is, only if the investor closes on a property, what fee should I expect? 

I am thinking perhaps .5% of the sales price to as much as 1% of the sales price if I drive over 50 miles (one way) to visit a property.