Now I do know my cash flow number with all expenses, including the ones listed, and I typically end up with a net of $400-$500 per month even though I'm collecting the excess as well. 

But yes, we put a TON of work into this and we have never received a penny of income until last week (even ended up paying the income tax out of our own pockets) so it's time to collect on the work!

Makes sure that you collect your closing statement the day before closing, as otherwise closing will be delayed.

Turnkey operators don't work like that and they are more like a broker collecting a fee for their work (regardless of the long-term performance).

That way, you could live in one, purchase with little down since you can use a primary residence loan with a low down payment, and collect rental income on the other 3 units.

Let her know you'll send her to collections if she refuses. 

To avoid opening a bank account and following all the rules that come with collecting and holding a security deposit I figured id just treat last months rent as security deposit.

What’s the legal way to collect payments from roommates that live with me in the same house? 

It's completely legal that's what I do I pay the bills to the utility company and send a copy to the tenants and collect the 60/40 split from them each month

The LLC collects rent, pays expenses, and distributes funds to the owners based on your partnership agreement.