so many 3bd/1ba Units

[Mercedes Williams]

From the Kansas city, MO/KS area. How costly would it be to renovate both units for another 1/2 bath. For some reason in my area there are a ridiculous amount of properties with 3 or 4 bd and only 1 bathroom. This seems very odd to me. would it be worth it to add a 1/2 bath or just find something else. Since plumbing is the most costly renovations i was wondering how i should go about it from a starting investors prospective.