so they got 30% of value or 30% of Principle Balance

I doubt it.I suspect that most people use "cash flow" to mean what they think will be left in their bank account at the end of the year since they're not really concerned with accounting principles.  

Make sure that dad understands that this could be an illiquid investment for some time (I am sure your dad is smart, but you ALWAYS want to talk through Goals and Objectives BEFORE signing). 

As much as you want to stand for principle, it's the best approach to take.

Yesterday I got a signed agreement in the mail for a peace of land that is worth$5,000 that I am purchasing for $700.00 ,last week I got a $4,000 vacant lot for $500.00 +$200 back taxes ....I'm not the smartest person in the world but i'm pretty sure thats better then 6% I dont feel the least bit worried that I am doing anything wrong because I am a principle in the transaction. 

Here are my rankings from the last couple of weeksReal Crowd Ames Holiday Inn 4.5 Great location, 25% equity by sponsor, assuming debt (below market rates), high cash flow and another 5% a year in principle paydown.  

But more caught up in chasing shinny objects.  

In addition, I am researching online real estate courses in order to get a better understanding of the core principles.

Regrettably, their parents knew very little about money, so they couldn’t show them how to take advantage of their situation, which begs the question; are you teaching your kids sound principles about how to use and invest money?

@Jd Martin  I sometimes get a serious case of shinny object syndrome.. but in real estate that can be good thing.. find a market before someone else and exploit it on the run up... there is so much more to real estate than simply buying and renting a SFR or small multi..there is a big wide world out there of opportunites..