However, I am a numbers guy and base all of my investment decisions based on the numbers.  

You may want to seek out an attorney if you are looking for a registered agent or if you are going into business with a partner, because there can be numerous decisions that need to be made regarding the arrangements between the members of the LLC.Asset protection problems usually arise when you don't run the company as a separate entity.

To me, that looks like a big red flag that says that you made the right decision by walking away.

Considering they all have the same term of 12-18 months, and a projected net profit of 1.5x equity multiple, (a $1MM project, with a $1.5MM ARV) which would you rather:-Debt securities, secured by the property, monthly returns, typically at a higher rate, no accrued returns or profit sharing; or,-Preferred equity, higher risk, quarterly returns at a lower current rate, with a set accrued return which brings your total returns higher than would be with debt; or,-Common equity, highest risk, quarterly returns similar to preferred equity, profit sharing upon sale or refinancing the property based on your % equity ownership.Also, any additional information you're willing to share would be great such as the type of deals you've invested in and the performance/results of those investments, especially if they influenced your decision.

I can't just sit around the house, so I am sure I will be doing something if I leave the 9-5, but I don't want to factor that unknown income in the decision making process.

I have no qualm with making decisions, but If you do not understand it, it's NOT going to benefit you! 

I can only speak to my situation in helping you make a decision.  

One could simply be he doesn't have the money to make his note payment, and no one has come along to solve his problem for him (not everyone makes rational decisions all the time).

Assessing all of your resources, especially experience and time, is crucial to making the best decision for you.

Remember you're also interviewing him to see how he can help you reach your goals (if you make money, he makes money).I would also recommend meeting at least three brokers before making a decision.