If you replace it in 5 years, you'll be repairing any damage done on the inside, and you'll be coming out of pocket for all of it...plus interest if the source is a loan. 

When I look at zillow or other sources it suggests a monthly rental of closer to $1800. 

At least from the sources if seem so far.What would guys consider fair “walk away” money on let’s say, a $500k home with $200k in equity and $50k and back payments?

This could have larger consequences for the top end of the market, where financial market wealth is often used as a source of funds for luxury homes, second homes, and investment properties.

Doing my first house hack in Chicago and just looking at all difference sources for deals. 

New and learning is good.There are different types of mortgage money, different sources of mortgage money and different ways mortgage money is amortized or calculated.There is regular Fannie Mae/Freddie Mac money. 

My sources tell me the Israelis have one that works on mammals. 

Also, there's the risk of major events coming up (like the corona virus) that could wipe you out if you don't have another source of income (i.e. your job). 

I work with an excellent lender, Mike Spindler at AMEC Homes loans, and also think @Sean Blomquist at Pine Financial is an excellent source for hard money loans - and his meetups are very informative for how it all works.

Many expert sources have largely avoided the actual numbers of deaths caused from Covid-19 v.s. the flue and factually which is more a threat to human life.