Buying properties while many renters are financially unstable

Hey team,

I'm a new investor in Boston and I am excited to get after some creatively financed buy-and-hold deals. I bought my first investment last year and feel pretty confident in my deal finding, renovating and management chops. My only hesitation in jumping in to find my second deal right now is the volatility in the job market. I live in Boston where my PITI is really high and I don't have enough cash to keep up with the fixed cost of a multi-family building without rents. For context, my cashflowing duplex right now is about $4k/month before any repairs.

My worst fear is buying a property, getting tenants and having those tenants lose their jobs unexpectedly (i.e the virus gets worse) and leaving me footing the full bill every month.

Does anyone have advice on how to qualify deals/tenants in a fluctuating market?

Any advice is greatly appreciated!