Found a place! Has anyone converted a two family into a 3 family?

[Steve Candor]

It's a 2 family property. Third Family is already built. I would need to separate 2nd floor electric with 3rd floor electric. I was going to run conduit on the outside of the building and run it into the 3rd floor. For heat they just use electric heaters. I may or may not convert to gas. 

Most important - is I need to install a stove (and the hookups) and fridge. As well as a kitchen sink. (bathroom is already up) Whats roughly the cost to do this job in the Northeast (in Mass)?