. $200/month/unit seems to be a common example).

The common theory is people “wait” for a crash but when it comes, they are unable to act because of fear or lack of liquidity or often both.

Also some Multifamily Properties the  landlord pays the electric and gas for the common areas like stairwells.  

(Like common steps it took to acquire)

What's more common if the condition of the place is terrible is to get a $100K-assessed place down to maybe $70K if you paid $50K of so for it.

It appears to be common for many of the buildings to be divided into many rooms boarding house style and you pay for a room w shared common area.

HOA's usually only have control of the outside and the common grounds of the property. 

If you find someone that will "do it all for you" - turnkey - they're making significant money off the deal one way or another, commonly on the spread of the purchase and sale of the property.

There are much more to these stories, however, the common thread that I saw with both of them is that they didn't consult a mentor or coach in their strategies in acquiring these properties.  

Everything is negotiable and asking for closing cost help is very common in the first-time buyer market, at least in the Baltimore metro area.