This prevents them from leaving since the neighborhood is safe for their children and also prevents them from making that monthly payment.

What prevent from processing through conventional mortgage?

Supposedly that helps prevents tenants from trying what your tenant did and I've done that ever since for me and my clients. 

My mom & I started playing that cash flow game from Kiyosaki for awhile and I was looking forward to playing it with other people locally but this pandemic is preventing me from doing just that.Will have to jump on that opportunity when it presents itself in the future!

I ask because NY's Tenant Safe Harbor Act prevents evictions during and after the pandemic due to not paying rent resulting from COVID related "financial hardships".1) "Financial hardships" seems very subjective.2) You can currently still take them to court for a money judgement on owed back rent after COVID, but you can't evict based on lack of payment.

Tree roots can be another source of cracks in a foundation.You mentioned it's an older house, in which case 5% might not be enough for ongoing repairs budget.

After updating I would then be able to rent the place out for $1200 a month.Again, these are made up numbers, I'm just curious if this idea would work or is there something I am completely missing that would prevent me from doing this?

@Marco Morkous Silly/stupid question, given that you’ve had a pro work on what everyone appears to presume is a utility sewer line, but: are you sure that the house is not on a septic tank, with the root of the problem there?

By considering the question he asked, I must admit there is a sense of the fear of the unknown here that prevents me from considering it whole-heartedly. 

My Debt To Income ratio is currently around 50%, which prevents me from taking out a conventional loan.