I KNOW that market very well, having built all types of projects from SFR, MFR, subdivisions, office parks, medical/dental, retail/office condos, etc.

the turn key marketers  ( just think as real estate brokers nothing more nothing less)  their clients are the guys and gals that live in the market buy the homes that need rehab and then resell.. they are flippers.. then many will have in house management which makes them " turnkey "  the real risk as Ivan is talking about is buying low end C class.. for most out of state investors over time the expense's create an investment that maybe you would not have made... where as A and B class tend to run fine in any city you buy them in or anyone you buy them from... you can go right on MLS and buy them.. 

Also, you not spending all the money on the repair does not create income for you. 

Have you spoken with a lawyer on the process of creating the GK and how to wrap investment property with a Non-PR? 

for that matter, so that I can rent it out to tenants and create a viable stream of income. 

I'm very early on, NOT actually engaged in searching for the a building today.My COH will be $500-800K, I want to be totally involved with every aspect of the transaction, the ownership.I will create a high-quality place to live, a destination to be desired.In your opinion:What are the questions I should be asking?

The past is the past.I would also point out two things based on your comments that may indicate why you chose to go in a different direction.  1) The use of a self-directed IRA custodian - where they have to sign every document and cut every check - is not well suited for a portfolio that involves a lot of assets or assets that create a lot of transaction activity. 

If you have no clue on what you are doing, spend the money and time you otherwise would have on creating an LLC towards getting an education on the correct way to put a property under contract. 

You may payments and the payoff to the LLC.If they money is still in the old 401k's and they don't want to take a distribution, they would each create an SDIRA and an IRA LLC. 

You've created an additional $4.6 million in value by spending $1 million in renovations.