Turning 4-plex into Duplex

[Benjamin Danard]

My father owns a 4-plex in central CT. Two houses and 2 apartments. The main houses are 3 bed, 2.5 baths. These are side by side. In each side's basement is a studio apartment (full bath, no kitchen). These apartments share electricity and heat with their respective sides. These apartments are a problem. One sits empty because the family living above did not want someone living below them. The other side has someone in the apartment and has only been able to attract a rotating group of young adults. It would be fairly easy to combine the apartments into the rest of the house to create another bedroom/office/den/in-law apartment. Has anyone else had experience with combining units? Was it a good idea?