There are often unexpected expenses, and you want to make sure you have enough cushion to get through those surprises.Given the current low inventory environment, I would say securing a good deal is challenging (though not impossible) in general.

In Columbia, finding a small multi-family property that makes sense numbers-wise can be difficult, but not impossible (low supply).

Impossible to guestimate rehab costs, could vary wildly. $30K should be more than enough for fresh paint and flooring and some other odds and ends, but if you need dry wall, cabinets, countertops, mechanicals etc it could get much pricier. 

Some of the assumptions appear likely as 7 inspections out of 7 all revealing major issues is not impossible, but at best unlikely.The question really is the severity of the problems that the inspection revealed.

.- Almost impossible to get any kind of unit damage paid for beyond what you have in a security deposit The rest of your statements about the homes needing a ton of work, contractors costing the same, and dealing with properties that are very tough to force appreciate are spot on.I personally do not invest in Section 8 housing anymore because they are normally cash flow purchases.  

A lot of my friends and other new grad young professionals seem to congregate in areas like Midtown and lower Manhattan or in Williamsburg/Bushwick and Downtown Brooklyn.I know house hacking isn't impossible in NYC, but my most ideal areas with people my age and high traffic are also everyone else's ideal places to live, and are much harder to house hack.

Below is a diagram illustrating the three main tenant segments in Las Vegas.If you unknowingly purchased a property that attracts the Transient tenant segment, turning a profit will be nearly impossible due to high vacancy costs.

STR's aren't impossible here, but depending on the area, you'll find them to be extremely seasonal.Other strategies that have worked for me and my clients is the MTR route, there's a robust hospital system in both NYC & LI that is always hiring contracted nurses for 3-6 months contracts. 

Are. next to impossible to achieve equitably.3.  

That way for developer putting in extra 100k in TI they get 250k more (hopefully) when they sell.5 years or less remaining on the lease those are almost impossible to finance and most are cash offers.