These are multifamily properties with multiple kitchen and laundries.   

For example, the layout of one kitchen might lend itself to adding a dishwasher easily.

*Note that we interchangeably use the labels: Lodging House = Rooming House = Single-Room Occupancy (SRO) = Co-Housing PropertyThe building has 3 kitchens and 4 full bathrooms, on 4 floors:3rd floor: The 3rdfloor is ‘off-limits’ to the 1st and 2nd floor tenants, so the two 3rd floor tenants enjoy the exclusivity of their own entrance, and a kitchen and bath shared only with one other unit, plus some distant ocean and Boston skyline views.2nd & 1st floors: Eleven units share 1 kitchen and 2 full bathrooms, one on each floor.

Plan is to wall it off and convert to a 4br/2ba,  update existing bath and kitchen, new floors,  interior and exterior  paint.

@Ariel HernandezSo many chefs in the kitchen.

We completely remodeled the kitchen and bathrooms.

Upstairs (separate space with kitchen would rent for $500- as I already have someone lined up for it.Purchase price about 230k.

I would not add much, a simple bedroom, bathroom, kitchen, and hvac.Another aspect of this deal is that the building is listed as a historic building and thus could qualify for some grants. 

I've been slowly updating -- new kitchen and bath in one unit, Fresh paint throughout, etc

Put locks on each bedroom door so individual tenants have security of their personal belongings.You need a really good set of rules regarding shared common space, cleaning, kitchen use, bathroom use, etc.Be very clear about the rules up front, and selective about who you put in there.