The truth is, you could read 100 books and still not know enough because certain things need to be learned through trial-and-error.

Ive found through trial and error, I simply do not work with out of state investors, period.

I did and it's given me all the resources I need to be successful so that the pressure on me is to simply do the work and not to trial and error as much. 

While protecting yourself against the local market and currency variations, you will also protect against declines in a single asset class.

The truth is, you could read 100 books and still not know enough because certain things need to be learned through trial-and-error.

I would assume there's some trial and error to it, but if anyone has any helpful tips it would be much appreciated!

The truth is, you could read 100 books and still not know enough because certain things need to be learned through trial-and-error.

There is far too much variation in what people call "cashflow" to have a standardized profit margin here, but in general I would say that if you have accounted for industry standard and market specific vacancy, repairs, maintenance, management, taxes and insurance and you are profiting 40% after debt you're sittin' pretty!

Most typical HMLs will be structured similar to what @Jon Holdman described, each with their own variation on the basics. 

Other than that, might be short term random variation.