If you are talking about renting the property out, yes, Baltimore County law states that in a rental, if it is not a rooming house, no more than two unrelated people are allowed to live in the property.
Towson University lays it out very well on their website:
They state there: "In Baltimore County, no more than 2 unrelated people may live together in a single-family dwelling. Houses converted into apartments units are included. In that case, only two per apartment are allowed.
In Baltimore City, the codes are more complex, but in basic, no more than 4 unrelated people may live together in a single-family dwelling."
I hope this helps!
Keller Williams Excellence Realty