Since you retain control of your money, how does one consistently maintain 30-50% cash on cash return? 

Based on what you wrote, it sounds like your project partner lost control and got pushed over by the contractors.

SFHs are largely exempt from many regulations such as rent control.

He is knowledgeable but he has no control over the GP.

Also control the thermostats so the tenants don't jack up the heat in the winter giving you a massive bill.

You have more control of your time when working with sellers as opposed to buyers.

It means instead of having one or a few things that you have NO control of what so ever, you now have several things you have NO control of what so ever.

The answer is that if the lender that's doing the hard money loan is only funding the purchase and not the rehab, they then have less oversight of the project since they're not doing the draws, and thus not seeing the progress of the project and having control of the funds or draws from the rehab to make sure the project is progressing.

Now it's an out of control machine with a lot of financial incestuous relationship in the tupperware farm.I like your analogy.

If you want to grow, then scaling within control is good.