We did one smart thing--we financed with long-term debt and we used low leverage (60% +/-) so we have a wide margin of safety and no threat of a loan maturity until 2031, so we have plenty of time to ride this out until the next market cycle. 

Income: Strong and can be used as a safety net if if needed.My main question is: Cash vs.

The beauty is if rents can keep up with expenses then PI remains constant and that is where the appreciation of increasing rents becomes a good thing.Sure overall costs can come in below 50% then that is a safety net.

Tenant B replied that he was tired of “this” and that he wanted his lease terminated because he feared for his safety.

There are a couple spots around town I would avoid, but I chose to raise my kids here and have never been concerned for their safety. 

When homes are pulled in a safety inspection must be paid for prior to the home being occupied.

While proximity to developing scenes and amenities suggests upward potential, the nearby "war-zone" area could raise significant concerns regarding safety, tenant quality, and property value stability.

Such a short timeline doesn't give you any real margin of safety since you get out of debt, then right back into debt shortly thereafter.This depends on your current interest rate though.

She has a co-signer willing to sign, but I'm hesitant with her age/safety (the garden unit has a steep staircase) and with rent being $1800 is that doable for her?

You could only evict for health and safety issues.