Go to the DIG website at http://digonline.org/Select the "Benefits" menu, and from that menu pick "Merting Downloads"; that will take you to the DIG Store (the naming behind this is goofy IMO).Search there for "Dennis Cline" and you will find the materials from his workshop he did for DIG. $179 price for both DIG members and non-members. 

Optimize opportunities To those who don’t speak it, the legal and tax side of real estate investing can seem impenetrable and its ideas too complex to grasp.

It sounds like the problem may be that you've hired TD Ameritrade to serve as trustee, recordkeeper and/or administrator for your solo 401k plan, and, in that capacity, they are creating obstacles to your investing outside of their "menu." 

I believe the optimal utilization for consumer loans is about 20 - 30%.

This is fine if you plan to live on the $100/door, but if your goal is to immunize yourself from inflation risk owning these properties is sub-optimal.

Is this the most optimized strategy to achieve strong cash flow?

What's the optimal equity range (ex: 50 - 80, 40-75, etc.) that I should include in my search 2) I have 400 leads based on our target area.

Ask yourself what the advantage to being able to drive to a sub optimal market is.

Optimizing their willingness to pay me is part of customer relationship management.

It's one of the links in the top menu bar when you log in.