I do not have my numbers as well organized as @Greg Scott but my estimate is upper 20% annual return on average.The 3 i am currently invested in, one seems likely to produce an outstanding return (High risk, high reward), one is conservative and is performing to projections, and one i have significant concerns about but has not had a capital call.  

Prior to these neighbors, the unit above was occupied, and we never experienced any problems.We’ve spoken to management multiple times, but they’ve been completely unhelpful and have taken no meaningful action and even told us that we are making the noise up, inspite security having been to our apartment numerous times wittnessing the noise. 

My perceived risk at the time whether, right, wrong, or indifferent, the reward for me just wasn’t there.

Property management is one of our core services, and we've worked with numerous property managers over the years.

Being nice to lazy investors, just rewards bad behavior and doesn't push them to be more resourceful - and hence more successful.It is a free country though, so best of luck with your approach:)

The miners are compensated on transactions and more importantly rewarded with coins.

I left numerous contact me letters to speak to the owner to discuss options and potentially cash for keys.

When successful it is quite rewarding and can lead to favorable basis and financing opportunities but there are certainly risks and its important to have plenty of reserves and be realistic with time frames.

The reason for this is that RE market prices are based on numerous criteria.

Numerous ways assets can, legally and illegally be placed beyond the reach of judgement creditors.