When it comes to rehabs, I’ve seen in the forums a good rough estimate is $20-$100/sqft, dependent supply the severity of the rehab.

With any house-hack comes some sacrifices as well: factors such as location, value-add vs turnkey, size, rent to price ratio, short-term vs mid-term vs long-term renting, and your ability to jump into the next one quickly all depend on you as the buyer. 

I locked my interest rate and I understand you normally can't get out of that rate.

There is not one method to doing this and it mostly depends on how much paperwork you want to do.

Would you rather pay a highrt monthly PM rate and have no added on fees?

I would recommend you expand your search area as well depending on your budget.

I think my take so far with it is that it can be useful but it is still a bit stiff in its answers depending on what you are trying to achieve with it and you may have to do some secondary work with your results.

I would say it depends.

What did you pay, what is market rate rent, how much equity do you have, and what interest rate/loan type do you have?

With conventional mortgage rates hovering around 7% for 30 years… cash flow basically happens at 6.5% cap rate and above.