How to Find Out if Home Can Be Converted to Triplex/Quad

[Kennesha VanBurch]

Hi all,

My husband and I have a contract on a multi-family home in Baltimore that was advertised as a triplex. When we toured the home, in addition to three apartments, we were happy to find a two-bedroom basement that could be renovated into a fourth apartment. I would like to know:

1) How do we find out if the home is legally-zoned as a triplex

2) How do we go about learning if it can be legally zoned as a Quad? 

Thank you for your advice in advance!