In my personal opinion I do not believe that someone would cut costs and want to rehab this place to bandaid the problem of leaks on the took which goes down into the walls and light fixtures, plus an unfished bathroom-like area that's exposed sewer drain and plumbing, someone couldn't just temp fix it to make it livable because I believe its unsafe the air quality is bad when the furnace kicks on it sets off smoke alarms so they leave it off.....

Put water alarms or sensor shutoff valves in in high risk areas such as with hot water heaters, washers, fridges with water lines, dishwashers, and in cabinets under sinks.  3. install a DWIP type pan under dishwashers, washers, and hot water heaters so leaking water will run in a direction where it is more likely to be seen and not cause damage. 4.

I don't want to sounds alarming here but these are all pretty fundamental items that would need to be discussed BEFORE you make an offer on a property. 

Motion activated barking dog alarm ( yep, they make them ) 2.

Also a good reason to make sure any home has a CO detector installed at the lowest point possible; a ceiling-mounted CO detector won't alarm until it's too late.

Tapping PEX into existing plumbing is pretty easy as long as they were semi-competant and I don't find it super alarming that permits were not pulled.

So I have some old 401ks that i'm planning on cashing out (I know that's a little alarming but after tons of debating and research I think its the best use of the funds) to use on my first BRRRR.

Do you use a security alarm and does it help?

Personally, I think your calculations are a bit alarming because I do not see any reserve savings.

They also make water alarms (check amazon for the brand) that link to your cell phone and alert you.