There are habitability standards specific to each location that you as the landlord would be responsible for. 

The Core 4 Members Vital to a Profitable Long-Distance Real Estate Investing Team on BiggerPockets provides valuable information.

The neighborhood is vital to your success but an agent has to tip toe around Federal and State Laws to not say, "this is a bad neighborhood."

If I were you I would make it a habit to raise rents each year to avoid situation like this were your now $600 lower than where you want to be. 

In addition to ensuring that the room is built to the proper load bearing capacity as @Mike Reynolds mentioned, you should also keep in mind that you need a second egress point, such as an egress window, for any habitable room especially if it is designed for sleeping purposes.

Focus on essential repairs to make the property habitable and attract new tenants.

I personally like small controlled necessary government for vital services that are needed and minimal but importation regulation on the private sector side.

If your looking to house hack I recommend you research the VA habitability requirements.

For instance, a lender might require a minimum DSCR of 1.25, meaning the property's income must exceed its debt obligations by 25%.Significance of DSCR LoansDSCR loans play a vital role in commercial real estate financing for several reasons:Risk Assessment: DSCR provides lenders with a quantitative measure of a property's ability to generate income and repay debt.

In other words, if the property is habitable and no longer dangerous and someone could live there, it’s probably also ready for lease.Once the property is in service you can finish the renovation and deduct some of the costs as repair and maintenance expenses in the current year.