Great way to increase your exposure and learning. Get to be involved in many more projects without getting tied down with the mundane steps. But I would think differently about fees. Do you really make a set amount every hour you are on one of your jobs? Most actual profit is made in design phase, where knowledge comes into play. Organization is another phase where experience pays off. And the mundane on the job installation is the lowest per hour real profit, because of the high cost of labor & materials.
You would want the class of person that wants to do the job right, but enjoys or economically needs to do it himself. Off the top of my head, I would sell this as a basic fee, plus an hourly fee. The basic fee is for your knowledge and experience (probably a percentage of the project cost if you did it yourself), the hourly fee is for the time spent in conveying this advice and criticizing their progress. Some would just want initial advice, but some of these will take twice as long as others; some might want you to criticize after each step of project so they are sure they are procceding properly.
Around here in maintenance work, most of us will consult for $35-40/hr, but if homeowner is really interested, price will quickly go down to $25-30. It makes it fun to find those who appreciate and really listen to your input. Your $50/hr, 2 hr min may scare off some as too costly - any question I have during the project will cost $100?
North central Indiana
<a href="http://members.aol.com/groundkprs/Entry/Educate.html">Learn About Turfgrass</a>